Enum "ModCallbacks"

This is a list of all new callbacks added by REPENTOGON.

Modified Old Callbacks

MC_USE_PILL

MC_USE_PILL now passes PillColor as an argument. Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
10	MC_USE_PILL	(PillEffect Effect, EntityPlayer Player, UseFlags Flags, PillColor Color)	PillEffect	void

MC_PRE_PLAYER_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
33	MC_PRE_PLAYER_COLLISION	(EntityPlayer Player, Entity Collider, boolean Low)	PlayerVariant	boolean or table

MC_PRE_TEAR_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
42	MC_PRE_TEAR_COLLISION	(EntityTear Tear, Entity Collider, boolean Low)	TearVariant	boolean or table

MC_PRE_FAMILIAR_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

For example, you can return { Collide=true } to make a familiar to collide physically with something (like an enemy, which they don't normally do) without skipping on-collision code (like you would by returning false).

ID	Name	Function Args	Optional Args	Return Type
26	MC_PRE_FAMILIAR_COLLISION	(EntityFamiliar Familiar, Entity Collider, boolean Low)	FamiliarVariant	boolean or table

MC_PRE_BOMB_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
60	MC_PRE_BOMB_COLLISION	(EntityBomb Bomb, Entity Collider, boolean Low)	BombVariant	boolean or table

MC_PRE_PICKUP_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
38	MC_PRE_PICKUP_COLLISION	(EntityPickup Pickup, Entity Collider, boolean Low)	PickupVariant	boolean or table

MC_PRE_KNIFE_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
53	MC_PRE_KNIFE_COLLISION	(EntityKnife Knife, Entity Collider, boolean Low)	KnifeSubType	boolean or table

MC_PRE_PROJECTILE_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
46	MC_PRE_PROJECTILE_COLLISION	(EntityProjectile Projectile, Entity Collider, boolean Low)	ProjectileVariant	boolean or table

MC_PRE_NPC_COLLISION

Now optionally accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity, such as dealing collision damage. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
30	MC_PRE_NPC_COLLISION	(EntityNPC NPC, Entity Collider, boolean Low)	EntityType	boolean or table

MC_ENTITY_TAKE_DMG

Now optionally accepts returning a table, with any combination of the following fields, to override the corresponding argument:

• Damage
• DamageFlags
• DamageCountdown

Modified values are passed along to the remaining callbacks. Returning false to cancel the damage still skips the remaining callbacks.

ID	Name	Function Args	Optional Args	Return Type
11	MC_ENTITY_TAKE_DMG	(Entity Entity, float Damage, DamageFlags DamageFlags, EntityRef Source, int DamageCountdown)	EntityType	boolean or table

New Callbacks

MC_PRE_ADD_COLLECTIBLE

Accepts a table of parameters: {Type, Charge, FirstTime, Slot, VarData, Player}

Alternatively accepts a CollectibleType to change the type without changing any other parameters or a boolean to cancel the addition altogether (false) or force it to happen skipping the following callbacks (true).

Example Code

This code will transform every collectible into Money = Power once the player picks it up.

function mod:myFunction(Type, Charge, FirstTime, Slot, VarData, Player)
    return CollectibleType.COLLECTIBLE_MONEY_EQUALS_POWER
end
mod:AddCallback(ModCallbacks.MC_PRE_ADD_COLLECTIBLE, mod.myFunction)

This code will force active items to be uncharged on pickup.

function mod:myFunction(Type, Charge, FirstTime, Slot, VarData, Player)
    return {Type, 0, FirstTime, Slot, VarData}
end
mod:AddCallback(ModCallbacks.MC_PRE_ADD_COLLECTIBLE, mod.myFunction)

ID	Name	Function Args	Optional Args	Return Type
1004	MC_PRE_ADD_COLLECTIBLE	(CollectibleType Type, int Charge, boolean FirstTime, int Slot, int VarData, EntityPlayer Player)	CollectibleType	table or CollectibleType

MC_POST_ADD_COLLECTIBLE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1005	MC_POST_ADD_COLLECTIBLE	(CollectibleType Type, int Charge, boolean FirstTime, int Slot, int VarData, EntityPlayer Player)	CollectibleType	void

MC_POST_BACKDROP_PRE_RENDER_WALLS

ID	Name	Function Args	Optional Args	Return Type
1109	MC_POST_BACKDROP_PRE_RENDER_WALLS	void	-	void

MC_PRE_BACKDROP_CHANGE

Accepts an integer to change BackdropType.

ID	Name	Function Args	Optional Args	Return Type
1141	MC_PRE_BACKDROP_CHANGE	(BackdropType Type)	-	(BackdropType Type)

MC_PRE_BACKDROP_RENDER_FLOOR

ID	Name	Function Args	Optional Args	Return Type
1107	MC_PRE_BACKDROP_RENDER_FLOOR	(ColorModifier ColorModifier)	-	void

MC_PRE_BACKDROP_RENDER_WALLS

ID	Name	Function Args	Optional Args	Return Type
1106	MC_PRE_BACKDROP_RENDER_WALLS	(ColorModifier ColorModifier)	-	void

MC_PRE_BACKDROP_RENDER_WATER

ID	Name	Function Args	Optional Args	Return Type
1108	MC_PRE_BACKDROP_RENDER_WATER	void	-	void

MC_POST_BOMB_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1237	MC_POST_BOMB_COLLISION	(EntityBomb Bomb, Entity Collider, boolean Low)	BombVariant	void

MC_PRE_BOMB_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1088	MC_PRE_BOMB_RENDER	(EntityBomb Bomb, Vector Offset)	BombVariant	Vector or boolean

MC_PRE_CHALLENGE_DONE

Executed before a challenge is marked as completed.

Returning false will prevent further execution of the challenge completion-tracking function.

ID	Name	Function Args	Optional Args	Return Type
1471	MC_PRE_CHALLENGE_DONE	(Challenge, EntityPlayer EntityPlayer)	Challenge	boolean

MC_POST_CHALLENGE_DONE

Executed after a challenge is marked as completed.

ID	Name	Function Args	Optional Args	Return Type
1472	MC_POST_CHALLENGE_DONE	(Challenge)	Challenge	void

MC_PRE_CHANGE_ROOM

Accepts a table of parameters: {TargetRoomIdx, Dimension}

ID	Name	Function Args	Optional Args	Return Type
1061	MC_PRE_CHANGE_ROOM	(int TargetRoomIdx, int Dimension)	-	table

MC_PRE_COMPLETION_EVENT

Can return false to cancel the completion event. Canceling it will prevent all marks and completion event related stuff to trigger for all players.

Triggers when a completion even gets triggered, getting as a parameter the code for the event in question.

ID	Name	Function Args	Optional Args	Return Type
1049	MC_PRE_COMPLETION_EVENT	(CompletionType Completion)	-	void or false

MC_PRE_COMPLETION_MARKS_RENDER

Can return false to prevent the completion marks from rendering.

ID	Name	Function Args	Optional Args	Return Type
1216	MC_PRE_COMPLETION_MARKS_RENDER	(Sprite CompletionMarksSprite, Vector RenderPos, Vector RenderScale, int PlayerType)	-	void

MC_POST_COMPLETION_MARKS_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1217	MC_POST_COMPLETION_MARKS_RENDER	(Sprite CompletionMarksSprite, Vector RenderPos, Vector RenderScale, int PlayerType)	-	void

MC_COMPLETION_MARK_GET

Can return false to cancel the completion mark.

Triggers when the player gets a completion mark, getting as a parameter the code for the mark in question and the playertype.

ID	Name	Function Args	Optional Args	Return Type
1047	MC_COMPLETION_MARK_GET	(CompletionType Completion, int PlayerType)	PlayerType	void or false

MC_POST_COMPLETION_MARK_GET

Triggers after the player gets a completion mark, getting as a parameter the code for the mark in question and the playertype.

ID	Name	Function Args	Optional Args	Return Type
1048	MC_POST_COMPLETION_MARK_GET	(CompletionType Completion, int PlayerType)	PlayerType

MC_CONSOLE_AUTOCOMPLETE

This is called whenever a function with the CUSTOM AutocompleteType enum is being entered into the console. Called every time the console input changes.

Accepts a table. The table can hold both string values, which will just add the string as a parameter in autocomplete for the command, and a table of two strings which will add the first string as the parameter, and second as a description. Description can be used in autocomplete as well, however pressing TAB will properly autocomplete using the ID, not description (Think the giveitem command, as an example- c1 would be The Sad Onion's "parameter" and The Sad Onion would be the "description", and both work. Pressing TAB will turn the command into give c1.)

REPENTOGON handles only showing options relevant for the given input- simply return a table of options, and REPENTOGON will take care of the rest.

ID	Name	Function Args	Optional Args	Return Type
1120	MC_CONSOLE_AUTOCOMPLETE	(string Command, string Params)	string Command	table

MC_PRE_DEVIL_APPLY_ITEMS

This callback is run when the game starts to tally up traditional items for devil deal calculation. This is called before the stage penalty.

Most items that affect devil deal chance perform their changes here.

Accepts a float to modify the chance in this step of the calculation.

ID	Name	Function Args	Optional Args	Return Type
1130	MC_PRE_DEVIL_APPLY_ITEMS	void	-	float

MC_PRE_DEVIL_APPLY_SPECIAL_ITEMS

Next, the game applies "special" items which bypass the stage penalty like Goat Head and Eucharist.

Accepts a float to modify the chance in this step of the calculation.

ID	Name	Function Args	Optional Args	Return Type
1132	MC_PRE_DEVIL_APPLY_SPECIAL_ITEMS	void	-	float

MC_PRE_DEVIL_APPLY_STAGE_PENALTY

Next, the game calculates stage penalty. If a deal spawned anywhere on the previous two floors, the game decays the resulting chance by either 50% or 25% depending on how many deals have been taken.

Important to note that even though the game displays a value of ~66% or ~33% for the 50% and 25% values, respectively, this is because devil chance is not clamped to a value between 0 and 1, and "100%" without items generally means a value of ~133%.

Accepts a boolean. Return false to bypass the stage penalty.

ID	Name	Function Args	Optional Args	Return Type
1131	MC_PRE_DEVIL_APPLY_STAGE_PENALTY	void	-	boolean

MC_POST_DEVIL_CALCULATE

This will override all previous calculation values, ultimately dictating the devil chance.

Accepts a float to modify the chance.

ID	Name	Function Args	Optional Args	Return Type
1133	MC_POST_DEVIL_CALCULATE	(float Chance)	-	float

MC_PRE_EFFECT_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1087	MC_PRE_EFFECT_RENDER	(EntityEffect Effect, Vector Offset)	EffectVariant	Vector or boolean

MC_POST_ENTITY_TAKE_DMG

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1006	MC_POST_ENTITY_TAKE_DMG	(Entity Entity, float Damage, DamageFlags DamageFlags, EntityRef Source, int DamageCountdown)	EntityType	void

MC_PRE_ENTITY_THROW

Accepts a Vector which will modify the velocity of the thrown entity.

ID	Name	Function Args	Optional Args	Return Type
1040	MC_PRE_ENTITY_THROW	(EntityPlayer ThrowingPlayer, Entity HeldEntity, Vector Velocity)	-	Vector

MC_POST_ENTITY_THROW

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1041	MC_POST_ENTITY_THROW	(EntityPlayer ThrowingPlayer, Entity ThrownEntity, Vector Velocity)	-	void

MC_POST_FAMILIAR_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1235	MC_POST_FAMILIAR_COLLISION	(EntityFamiliar Familiar, Entity Collider, boolean Low)	FamiliarVariant	void

MC_POST_FAMILIAR_FIRE_BRIMSTONE

Called when a familiar fires a brimstone laser.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1261	MC_POST_FAMILIAR_FIRE_BRIMSTONE	(EntityLaser Laser)	FamiliarVariant	void

MC_POST_FAMILIAR_FIRE_PROJECTILE

Called when a familiar fires a tear.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1252	MC_POST_FAMILIAR_FIRE_PROJECTILE	(EntityTear Tear)	FamiliarVariant	void

MC_POST_FAMILIAR_FIRE_TECH_LASER

Called when a familiar fires a Tech laser.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1262	MC_POST_FAMILIAR_FIRE_TECH_LASER	(EntityLaser Laser)	FamiliarVariant	void

MC_PRE_FAMILIAR_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1080	MC_PRE_FAMILIAR_RENDER	(EntityFamiliar Familiar, Vector Offset)	FamiliarVariant	Vector or boolean

MC_POST_FIRE_BOMB

Called when the player fires a Dr. Fetus bomb.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1253	MC_POST_FIRE_BOMB	(EntityBomb Bomb)	-	void

MC_POST_FIRE_BONE_CLUB

Called when the player fired The Forgotten's bone club.

This is only called when the club is initially spawned, not when swung or charged and shot.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1254	MC_POST_FIRE_BONE_CLUB	(EntityKnife Knife)	-	void

MC_POST_FIRE_BRIMSTONE_BALL

Called when the player fires a brimstone ball.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1256	MC_POST_FIRE_BRIMSTONE_BALL	(EntityEffect Effect)	-	void

MC_POST_FIRE_BRIMSTONE

Called when the player fires a brimstone laser.

This is also called for delayed brimstone.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1255	MC_POST_FIRE_BRIMSTONE	(EntityLaser Laser)	-	void

MC_POST_FIRE_KNIFE

Called when the player fires the knife from Mom's Knife.

This is only called when the club is initially spawned, not when charged and shot.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1257	MC_POST_FIRE_KNIFE	(EntityKnife Knife)	-	void

MC_POST_FIRE_SWORD

Called when the player swings the sword from Spirit Sword.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1258	MC_POST_FIRE_SWORD	(EntityKnife Knife)	-	void

MC_POST_FIRE_TECH_LASER

Called when the player fires a Tech laser.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1259	MC_POST_FIRE_TECH_LASER	(EntityLaser Laser)	-	void

MC_POST_FIRE_TECH_X_LASER

Called when the player fires a Tech X laser.

Returning any value will have no effect on later callback executions.

ID	Name	Function Args	Optional Args	Return Type
1260	MC_POST_FIRE_TECH_X_LASER	(EntityLaser Laser)	-	void

MC_GET_FOLLOWER_PRIORITY

Accepts FollowerPriority to give familiar priority. Can accept any int.

ID	Name	Function Args	Optional Args	Return Type
1063	MC_GET_FOLLOWER_PRIORITY	(EntityFamiliar Familiar)	FamiliarVariant	FollowerPriority or int

MC_PRE_GET_LIGHTING_ALPHA

Accepts a float to modify the lighting alpha. Generally this is between 0 and 1 but you can technically go higher than this.

ID	Name	Function Args	Optional Args	Return Type
1150	MC_PRE_GET_LIGHTING_ALPHA	(float OriginalAlpha)	-	float

MC_GET_SHOP_ITEM_PRICE

Called after the price for a shop item was calculated. Return an integer or PickupPrice to change the price of the item.

ID	Name	Function Args	Optional Args	Return Type
1066	MC_GET_SHOP_ITEM_PRICE	(int PickupVariant, int PickupSubType, int ShopItemID, int Price)	int	PickupVariant

MC_PRE_GRID_ENTITY_DECORATION_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1444	MC_PRE_GRID_ENTITY_DECORATION_RENDER	(GridEntityDecoration Decoration, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_DECORATION_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1445	MC_POST_GRID_ENTITY_DECORATION_RENDER	(GridEntityDecoration Decoration)	GridEntityType	void

MC_PRE_GRID_ENTITY_DECORATION_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1400	MC_PRE_GRID_ENTITY_DECORATION_UPDATE	(GridEntityDecoration Decoration)	GridEntityType	boolean

MC_POST_GRID_ENTITY_DECORATION_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1401	MC_POST_GRID_ENTITY_DECORATION_UPDATE	(GridEntityDecoration Decoration)	GridEntityType	void

MC_PRE_GRID_ENTITY_DOOR_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1446	MC_PRE_GRID_ENTITY_DOOR_RENDER	(GridEntityDoor Door, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_DOOR_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1447	MC_POST_GRID_ENTITY_DOOR_RENDER	(GridEntityDoor Door)	GridEntityType	void

MC_PRE_GRID_ENTITY_DOOR_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1402	MC_PRE_GRID_ENTITY_DOOR_UPDATE	(GridEntityDoor Door)	GridEntityType	boolean

MC_POST_GRID_ENTITY_DOOR_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1403	MC_POST_GRID_ENTITY_DOOR_UPDATE	(GridEntityDoor Door)	GridEntityType	void

MC_PRE_GRID_ENTITY_FIRE_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

Warning

Fire grid entities are largely unused, and in most cases you'll want to target the EntityNPC fireplaces.

ID	Name	Function Args	Optional Args	Return Type
1448	MC_PRE_GRID_ENTITY_FIRE_RENDER	(GridEntityFire Fire, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_FIRE_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1449	MC_POST_GRID_ENTITY_FIRE_RENDER	(GridEntityFire Fire)	GridEntityType	void

MC_PRE_GRID_ENTITY_FIRE_UPDATE

Accepts false to cancel the update.

Warning

Fire grid entities are largely unused, and in most cases you'll want to target the EntityNPC fireplaces.

ID	Name	Function Args	Optional Args	Return Type
1404	MC_PRE_GRID_ENTITY_FIRE_UPDATE	(GridEntityFire Fire)	GridEntityType	boolean

MC_POST_GRID_ENTITY_FIRE_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1405	MC_POST_GRID_ENTITY_FIRE_UPDATE	(GridEntityFire Fire)	GridEntityType	void

MC_PRE_GRID_ENTITY_GRAVITY_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1406	MC_PRE_GRID_ENTITY_GRAVITY_UPDATE	(GridEntityGravity Gravity)	GridEntityType	boolean

MC_POST_GRID_ENTITY_GRAVITY_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1407	MC_POST_GRID_ENTITY_GRAVITY_UPDATE	(GridEntityGravity Gravity)	GridEntityType	void

MC_PRE_GRID_ENTITY_LOCK_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1450	MC_PRE_GRID_ENTITY_LOCK_RENDER	(GridEntityLock Lock, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_LOCK_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1451	MC_POST_GRID_ENTITY_LOCK_RENDER	(GridEntityLock Lock)	GridEntityType	void

MC_PRE_GRID_ENTITY_LOCK_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1408	MC_PRE_GRID_ENTITY_LOCK_UPDATE	(GridEntityLock Lock)	GridEntityType	boolean

MC_POST_GRID_ENTITY_LOCK_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1409	MC_POST_GRID_ENTITY_LOCK_UPDATE	(GridEntityLock Lock)	GridEntityType	void

MC_PRE_GRID_ENTITY_PIT_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1454	MC_PRE_GRID_ENTITY_PIT_RENDER	(GridEntityPit Pit, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_PIT_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1455	MC_POST_GRID_ENTITY_PIT_RENDER	(GridEntityPit Pit)	GridEntityType	void

MC_PRE_GRID_ENTITY_PIT_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1410	MC_PRE_GRID_ENTITY_PIT_UPDATE	(GridEntityPit Pit)	GridEntityType	boolean

MC_POST_GRID_ENTITY_PIT_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1411	MC_POST_GRID_ENTITY_PIT_UPDATE	(GridEntityPit Pit)	GridEntityType	void

MC_PRE_GRID_ENTITY_POOP_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

Warning

This callback does not include the EntityNPC poops used by Tainted ???.

ID	Name	Function Args	Optional Args	Return Type
1456	MC_PRE_GRID_ENTITY_POOP_RENDER	(GridEntityPoop Poop, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_POOP_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1457	MC_POST_GRID_ENTITY_POOP_RENDER	(GridEntityPoop Poop)	GridEntityType	void

MC_PRE_GRID_ENTITY_POOP_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1412	MC_PRE_GRID_ENTITY_POOP_UPDATE	(GridEntityPoop Poop)	GridEntityType	boolean

MC_POST_GRID_ENTITY_POOP_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1413	MC_POST_GRID_ENTITY_POOP_UPDATE	(GridEntityPoop Poop)	GridEntityType	void

MC_PRE_GRID_ENTITY_PRESSUREPLATE_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1460	MC_PRE_GRID_ENTITY_PRESSUREPLATE_RENDER	(GridEntityPressurePlate PressurePlate, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_PRESSUREPLATE_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1461	MC_POST_GRID_ENTITY_PRESSUREPLATE_RENDER	(GridEntityPressurePlate PressurePlate)	GridEntityType	void

MC_PRE_GRID_ENTITY_PRESSUREPLATE_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1414	MC_PRE_GRID_ENTITY_PRESSUREPLATE_UPDATE	(GridEntityPressurePlate PressurePlate)	GridEntityType	boolean

MC_POST_GRID_ENTITY_PRESSUREPLATE_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1415	MC_POST_GRID_ENTITY_PRESSUREPLATE_UPDATE	(GridEntityPressurePlate PressurePlate)	GridEntityType	void

MC_PRE_GRID_ENTITY_ROCK_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1458	MC_PRE_GRID_ENTITY_ROCK_RENDER	(GridEntityRock Rock, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_ROCK_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1459	MC_POST_GRID_ENTITY_ROCK_RENDER	(GridEntityRock Rock)	GridEntityType	void

MC_PRE_GRID_ENTITY_ROCK_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1416	MC_PRE_GRID_ENTITY_ROCK_UPDATE	(GridEntityRock Rock)	GridEntityType	boolean

MC_POST_GRID_ENTITY_ROCK_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1417	MC_POST_GRID_ENTITY_ROCK_UPDATE	(GridEntityRock Rock)	GridEntityType	void

MC_PRE_GRID_ENTITY_SPAWN

This is called when a GridEntity is spawned outside of Room initialization.

Accepts false to cancel spawning the grid, a table of {Type, Variant, Vardata, SpawnSeed} to modify it, or a GridEntityDesc to override it entirely.

Warning

Desc will in most cases be nil. The exceptions to this are the poops spawned by Mole npcs, grids spawned by TurnGold, or lua-made spawns called with the new SpawnGridEntity(int GridIndex, GridEntityDesc Descriptor) override.

ID	Name	Function Args	Optional Args	Return Type
1100	MC_PRE_GRID_ENTITY_SPAWN	(GridEntityType Type, int Variant, int VarData, int GridIdx, int SpawnSeed, GridEntityDesc Desc)	GridEntityType Type	boolean, table, or GridEntityDesc

MC_POST_GRID_ENTITY_SPAWN

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1101	MC_POST_GRID_ENTITY_SPAWN	(GridEntity Grid)	GridEntityType Type	void

MC_PRE_GRID_ENTITY_SPIKES_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1432	MC_PRE_GRID_ENTITY_SPIKES_RENDER	(GridEntitySpikes Grid, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_SPIKES_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1433	MC_POST_GRID_ENTITY_SPIKES_RENDER	(GridEntitySpikes Grid)	GridEntityType	void

MC_PRE_GRID_ENTITY_SPIKES_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1418	MC_PRE_GRID_ENTITY_SPIKES_UPDATE	(GridEntitySpikes Spikes)	GridEntityType	boolean

MC_POST_GRID_ENTITY_SPIKES_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1419	MC_POST_GRID_ENTITY_SPIKES_UPDATE	(GridEntitySpikes Spikes)	GridEntityType	void

MC_PRE_GRID_ENTITY_STAIRCASE_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1440	MC_PRE_GRID_ENTITY_STAIRCASE_RENDER	(GridEntityStairs Staircase, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_STAIRCASE_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1441	MC_POST_GRID_ENTITY_STAIRCASE_RENDER	(GridEntityStairs Staircase)	GridEntityType	void

MC_PRE_GRID_ENTITY_STAIRCASE_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1420	MC_PRE_GRID_ENTITY_STAIRCASE_UPDATE	(GridEntityStairs Staircase)	GridEntityType	boolean

MC_POST_GRID_ENTITY_STAIRCASE_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1421	MC_POST_GRID_ENTITY_STAIRCASE_UPDATE	(GridEntityStairs Staircase)	GridEntityType	void

MC_PRE_GRID_ENTITY_STATUE_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1422	MC_PRE_GRID_ENTITY_STATUE_UPDATE	(GridEntityStatue Statue)	GridEntityType	boolean

MC_POST_GRID_ENTITY_STATUE_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1423	MC_POST_GRID_ENTITY_STATUE_UPDATE	(GridEntityStatue Statue)	GridEntityType	void

MC_PRE_GRID_ENTITY_TELEPORTER_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1452	MC_PRE_GRID_ENTITY_TELEPORTER_RENDER	(GridEntityTeleporter Teleporter, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_TELEPORTER_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1453	MC_POST_GRID_ENTITY_TELEPORTER_RENDER	(GridEntityTeleporter Teleporter)	GridEntityType	void

MC_PRE_GRID_ENTITY_TELEPORTER_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1424	MC_PRE_GRID_ENTITY_TELEPORTER_UPDATE	(GridEntityTeleporter Teleporter)	GridEntityType	boolean

MC_POST_GRID_ENTITY_TELEPORTER_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1425	MC_POST_GRID_ENTITY_TELEPORTER_UPDATE	(GridEntityTeleporter Teleporter)	GridEntityType	void

MC_PRE_GRID_ENTITY_TNT_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1436	MC_PRE_GRID_ENTITY_TNT_RENDER	(GridEntityTNT TNT, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_TNT_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1437	MC_POST_GRID_ENTITY_TNT_RENDER	(GridEntityTNT TNT)	GridEntityType	void

MC_PRE_GRID_ENTITY_TNT_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1430	MC_PRE_GRID_ENTITY_TNT_UPDATE	(GridEntityTNT TNT)	GridEntityType	boolean

MC_POST_GRID_ENTITY_TNT_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1431	MC_POST_GRID_ENTITY_TNT_UPDATE	(GridEntityTNT TNT)	GridEntityType	void

MC_PRE_GRID_ENTITY_TRAPDOOR_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1438	MC_PRE_GRID_ENTITY_TRAPDOOR_RENDER	(GridEntityTrapDoor TrapDoor, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_TRAPDOOR_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1439	MC_POST_GRID_ENTITY_TRAPDOOR_RENDER	(GridEntityTrapDoor TrapDoor)	GridEntityType	void

MC_PRE_GRID_ENTITY_TRAPDOOR_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1426	MC_PRE_GRID_ENTITY_TRAPDOOR_UPDATE	(GridEntityTrapDoor TrapDoor)	GridEntityType	boolean

MC_POST_GRID_ENTITY_TRAPDOOR_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1427	MC_POST_GRID_ENTITY_TRAPDOOR_UPDATE	(GridEntityTrapDoor TrapDoor)	GridEntityType	void

MC_PRE_GRID_ENTITY_WALL_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1462	MC_PRE_GRID_ENTITY_WALL_RENDER	(GridEntityWall Wall, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_WALL_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1463	MC_POST_GRID_ENTITY_WALL_RENDER	(GridEntityWall Wall)	GridEntityType	void

MC_PRE_GRID_ENTITY_WEB_RENDER

Accepts a Vector to modify render offset or false to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1434	MC_PRE_GRID_ENTITY_WEB_RENDER	(GridEntityWeb Web, Vector Offset)	GridEntityType	Vector or boolean

MC_POST_GRID_ENTITY_WEB_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1435	MC_POST_GRID_ENTITY_WEB_RENDER	(GridEntityWeb Web)	GridEntityType	void

MC_PRE_GRID_ENTITY_WEB_UPDATE

Accepts false to cancel the update.

ID	Name	Function Args	Optional Args	Return Type
1428	MC_PRE_GRID_ENTITY_WEB_UPDATE	(GridEntityWeb Web)	GridEntityType	boolean

MC_POST_GRID_ENTITY_WEB_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1429	MC_POST_GRID_ENTITY_WEB_UPDATE	(GridEntityWeb Web)	GridEntityType	void

MC_GRID_HURT_DAMAGE

Return false if entity or player should ignore damage from it.

ID	Name	Function Args	Optional Args	Return Type
1012	MC_GRID_HURT_DAMAGE	(GridEntity GridEntity, Entity Entity, int DamageAmount, DamageFlags DamageFlags, float Unknown boolean Unknown)	GridEntityType	boolean

MC_POST_GRID_HURT_DAMAGE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1013	MC_POST_GRID_HURT_DAMAGE	(GridEntity GridEntity, Entity Entity, int DamageAmount, DamageFlags DamageFlags, float Unknown boolean Unknown)	GridEntityType	void

MC_POST_GRID_ROCK_DESTROY

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1011	MC_POST_GRID_ROCK_DESTROY	(GridEntityRock Rock, GridEntityType Type, boolean Immediate)	GridEntityType	void

MC_HUD_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1022	MC_HUD_RENDER	void	-	void

MC_POST_HUD_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1024	MC_POST_HUD_RENDER	void	-	void

MC_HUD_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1020	MC_HUD_UPDATE	void	-	void

MC_POST_HUD_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1021	MC_POST_HUD_UPDATE	void	-	void

MC_IS_PERSISTENT_ROOM_ENTITY

Returning true allows entity to respawn.

ID	Name	Function Args	Optional Args	Return Type
1263	MC_IS_PERSISTENT_ROOM_ENTITY	(EntityType Type, int Variant)	-	boolean

MC_PRE_ITEM_OVERLAY_SHOW

Accepts an integer to change Giantbook

Alternatively accepts true to cancel item overlay show

ID	Name	Function Args	Optional Args	Return Type
1076	MC_PRE_ITEM_OVERLAY_SHOW	(Giantbook GiantbookID, int Delay, EntityPlayer Player)	Giantbook	Giantbook or boolean

MC_POST_ITEM_OVERLAY_SHOW

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1134	MC_POST_ITEM_OVERLAY_SHOW	(Giantbook GiantbookID, int Delay, EntityPlayer Player)	Giantbook	void

MC_POST_ITEM_OVERLAY_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1075	MC_POST_ITEM_OVERLAY_UPDATE	void	Giantbook	void

MC_POST_KNIFE_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1243	MC_POST_KNIFE_COLLISION	(EntityKnife Knife, Entity Collider, boolean Low)	KnifeSubType	void

MC_PRE_KNIFE_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1086	MC_PRE_KNIFE_RENDER	(EntityKnife Knife, Vector Offset)	KnifeVariant	Vector or boolean

MC_PRE_LASER_COLLISION

Runs right before a laser hits an entity. Return true to ignore the collision.

ID	Name	Function Args	Optional Args	Return Type
1248	MC_PRE_LASER_COLLISION	(EntityLaser Laser, Entity Collider)	LaserVariant	boolean

MC_POST_LASER_COLLISION

Runs after a laser hits an entity.

ID	Name	Function Args	Optional Args	Return Type
1249	MC_POST_LASER_COLLISION	(EntityLaser Laser, Entity Collider)	LaserVariant	void

MC_PRE_LEVEL_INIT

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1060	MC_PRE_LEVEL_INIT	void	-	void

MC_POST_LEVEL_LAYOUT_GENERATED

ID	Name	Function Args	Optional Args	Return Type
1099	MC_POST_LEVEL_LAYOUT_GENERATED	(LevelGenerator LevelGenerator)	-	void

MC_PRE_LEVEL_PLACE_ROOM

Return a room config to replace the room that will be placed

Warning

The new room shape must be the same, and the new available door slots must be compatible with the original room doors.

ID	Name	Function Args	Optional Args	Return Type
1137	MC_PRE_LEVEL_PLACE_ROOM	(LevelGeneratorRoom Slot, RoomConfigRoom RoomConfig, int Seed)	-	RoomConfigRoom Config

MC_PRE_LEVEL_SELECT

This callback is fired when the game selects which level (also known as stage) to load, usually when the player enters a trapdoor. The callback accepts two parameters:

• Level: the level selected by the game, as defined in the LevelStage enumeration.
• Type: the type of the level selected by the game, as defined in the StageType enumeration.

This callback can return either nothing or a table.

• Nothing: let the game continue with the level stage / stage type pair it selected;
• Table: must contain two fields (anonymous). The first field is the desired level stage, second field is the desired stage type.

If you return a table, Repentogon will check that the values fall in the allowed ranges for the level stage and the stage type.

Value ranges

Remember that the range of level types is not the same between normal / hard on one side and greed / greedier on the other.

Also remember that since Repentance the stage type value 3 is deprecated.

ID	Name	Function Args	Optional Args	Return Type
1104	MC_PRE_LEVEL_SELECT	(LevelStage Level, StageType Type)	-	void

MC_MAIN_MENU_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1023	MC_MAIN_MENU_RENDER	void	-	void

MC_PRE_MEGA_SATAN_ENDING

Called right before Mega Satan forcibly ends the game.

• Accepts true to suppress the ending, guaranteeing a portal to the Void while retaining the completion mark for this character.
• false or nil will have no effect. I might look into making false guarantee an ending?

ID	Name	Function Args	Optional Args	Return Type
1201	MC_PRE_MEGA_SATAN_ENDING	void	-	boolean

MC_MENU_INPUT_ACTION

Same as MC_INPUT_ACTION, but only works in the main menu.

ID	Name	Function Args	Optional Args	Return Type
1464	MC_MENU_INPUT_ACTION	(Entity, InputHook, ButtonAction)	InputHook	boolean or float

MC_POST_MODS_LOADED

Called after all Lua scripts have been loaded. Ideal for running code that is expected to run after all mods are initialized, but without the need for load order idiocy!

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1210	MC_POST_MODS_LOADED	void	-	void

MC_PRE_MUSIC_LAYER_TOGGLE

Accepts a music layer ID (enum pending) to change the layer, or a boolean to change the state of the layer: true to keep it running, false to stop it.

CurrentState returns true if the layer is going to be enabled, and false if it is going to be disabled.

ID	Name	Function Args	Optional Args	Return Type
1035	MC_PRE_MUSIC_LAYER_TOGGLE	(int ID, boolean CurrentState)	int	int or boolean

MC_PRE_MUSIC_PLAY_JINGLE

Accepts a Music to change the track

Alternatively accepts false to cancel the track

ID	Name	Function Args	Optional Args	Return Type
1094	MC_PRE_MUSIC_PLAY_JINGLE	(Music MusicID)	Music	Music or boolean

MC_PRE_MUSIC_PLAY

Accepts a table of parameters: {ID, Volume OR FadeRate}

Alternatively accepts a Music to change the track without changing volume or fade rate

Alternatively accepts false to cancel the track

Volume vs. FadeRate

This callback is called for both MusicManager::Play and MusicManager::Crossfade! IsFade is provided to distinguish the two.

Example Code

This code will replace all music track with the flooded caves theme (for better or for worse).

function mod:myFunction(ID, Volume, IsFade)
    return Music.MUSIC_FLOODED_CAVES
end
mod:AddCallback(ModCallbacks.MC_PRE_MUSIC_PLAY, mod.myFunction)

ID	Name	Function Args	Optional Args	Return Type
1034	MC_PRE_MUSIC_PLAY	(int ID, float Volume OR float FadeRate, boolean IsFade)	Music	table or Music or boolean

MC_PRE_M_MORPH_ACTIVE

This callback triggers when an active gets rerolled by 'M (trinket id 138) and allows for overriding its behavior.

• Accepts a CollectibleType to override the rerolled item id or false to prevent the active from rerolling entirely.

ID	Name	Function Args	Optional Args	Return Type
1190	MC_PRE_M_MORPH_ACTIVE	(EntityPlayer Player, CollectibleType Collectible)	-	CollectibleType

MC_PRE_NEW_ROOM

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1200	MC_PRE_NEW_ROOM	(Room Room, RoomDescriptor Descriptor)	-	void

MC_POST_NIGHTMARE_SCENE_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1102	MC_POST_NIGHTMARE_SCENE_RENDER	void	-	void

MC_POST_NIGHTMARE_SCENE_SHOW

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1103	MC_POST_NIGHTMARE_SCENE_SHOW	(boolean Unknown)	-	void

MC_POST_NPC_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1247	MC_POST_NPC_COLLISION	(EntityNPC NPC, Entity Collider, boolean Low)	EntityType	void

MC_PRE_NPC_MORPH

Accepts a table of parameters: {EntityType, Variant, SubType, Championid} or just {EntityType, Variant, SubType}.

Returning false cancels the morph.

ID	Name	Function Args	Optional Args	Return Type
1212	MC_PRE_NPC_MORPH	(EntityNPC NPC, int EntityType, int Variant, int SubType, int Championid)	-	table or boolean

MC_POST_NPC_MORPH

Runs after the Morph already happened.

ID	Name	Function Args	Optional Args	Return Type
1214	MC_POST_NPC_MORPH	(EntityNPC NPC, int PreviousType, int PreviousVariant, int PreviousSubType)	-	void

MC_NPC_PICK_TARGET

Called whenever an EntityNPC selects its target, such as when EntityNPC:GetPlayerTarget() is called.

Return an entity to make the NPC target that entity instead.

ID	Name	Function Args	Optional Args	Return Type
1222	MC_NPC_PICK_TARGET	(EntityNPC NPC, Entity CurrentTarget)	EntityType	Entity

MC_POST_NPC_DARK_RED_CHAMPION_REGEN

Runs right after a dark red champion regerates out of the goo form.

ID	Name	Function Args	Optional Args	Return Type
1223	MC_POST_NPC_DARK_RED_CHAMPION_REGEN	(EntityNPC NPC)	EntityType	void

MC_PRE_NPC_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1081	MC_PRE_NPC_RENDER	(EntityNPC NPC, Vector Offset)	EntityType	Vector or boolean

MC_PRE_NPC_SPLIT

Called when the game is about to decide whether or not an EntityNPC can be split, ie the Meat Cleaver effect.

Return true to prevent the split, false to allow it even if blacklisted, or nil to continue default behavior.

ID	Name	Function Args	Optional Args	Return Type
1191	MC_PRE_NPC_SPLIT	(EntityNPC NPC, boolean IsBlacklisted)	EntityType	boolean

MC_PRE_OPENGL_RENDER

Gets called right before the Manager::Render() function gets called.

ID	Name	Function Args	Optional Args	Return Type
1136	MC_PRE_OPENGL_RENDER	(VertexBuffer, int shaderId, RenderContext)	-	?

MC_PRE_PAUSE_SCREEN_RENDER

Can return false to prevent the pause screen from rendering. Doing so will also prevent the screen from darkening.

ID	Name	Function Args	Optional Args	Return Type
1218	MC_PRE_PAUSE_SCREEN_RENDER	(Sprite PauseBody, Sprite PauseStats)	-	void

MC_POST_PAUSE_SCREEN_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1219	MC_POST_PAUSE_SCREEN_RENDER	(Sprite PauseBody, Sprite PauseStats)	-	void

MC_POST_PICKUP_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1239	MC_POST_PICKUP_COLLISION	(EntityPickup Pickup, Entity Collider, boolean Low)	PickupVariant	void

MC_PRE_PICKUP_COMPOSTED

This callback is called when a pickup is consumed with the compost active. Accepts false to cancel the pickup getting consumed.

ID	Name	Function Args	Optional Args	Return Type
1267	MC_PRE_PICKUP_VOIDED	(EntityPickup Pickup)	PickupVariant	boolean

MC_PICKUP_GET_COIN_VALUE

Accepts int CoinValue to modify the amount of coins a coin can give you on pickup.

ID	Name	Function Args	Optional Args	Return Type
1250	MC_PICKUP_GET_COIN_VALUE	(EntityPickup Pickup)	CoinSubType	int CoinValue

MC_PRE_PICKUP_MORPH

Accepts a table of parameters: {EntityType, Variant, SubType, KeepPrice, KeepSeed, IgnoreModifiers} or just {EntityType, Variant, SubType}.

Returning false cancels the morph.

ID	Name	Function Args	Optional Args	Return Type
1213	MC_PRE_PICKUP_MORPH	(EntityPickup Pickup, int EntityType, int Variant, int SubType, boolean KeepPrice, boolean KeepSeed, boolean IgnoreModifiers)	-	table or boolean

MC_POST_PICKUP_MORPH

Runs after the morph already happened.

ID	Name	Function Args	Optional Args	Return Type
1215	MC_POST_PICKUP_MORPH	(EntityPickup Pickup, int PreviousType, int PreviousVariant, int SubType, boolean KeptPrice, boolean KeptSeed, boolean IgnoredModifiers)	-	void

MC_PRE_PICKUP_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1083	MC_PRE_PICKUP_RENDER	(EntityPickup Pickup, Vector Offset)	PickupVariant	Vector or boolean

MC_POST_PICKUP_SHOP_PURCHASE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1062	MC_POST_PICKUP_SHOP_PURCHASE	(EntityPickup Pickup, EntityPlayer Player, int MoneySpent)	PickupVariant	void

MC_PRE_PICKUP_VOIDED_ABYSS

This callback is called when a pickup is consumed with the abyss active. Accepts false to cancel the pickup getting consumed.

ID	Name	Function Args	Optional Args	Return Type
1266	MC_PRE_PICKUP_VOIDED_ABYSS	(EntityPickup Pickup)	PickupVariant	boolean

MC_PRE_PICKUP_VOIDED

This callback is called when a pickup is consumed with the void active or black rune. The IsBlackRune parameter indicates the source. If black rune is used, the callback gets fired both for pedestal items and for small pickups that turn into flies. Accepts false to cancel the pickup getting consumed.

ID	Name	Function Args	Optional Args	Return Type
1265	MC_PRE_PICKUP_VOIDED	(EntityPickup Pickup, boolean IsBlackRune)	PickupVariant	boolean

MC_PRE_PLANETARIUM_APPLY_ITEMS

After checking the amount of treasure rooms entered, the game applies flat item chances. This is where Crystal Ball, Magic 8 Ball and Sausage's chances get added, as well as Telescope Lens's additional 15% chance.

If you're looking to add an item like Telescope Lens which modifies the base chance, have a look at MC_PRE_PLANETARIUM_APPLY_TELESCOPE_LENS instead.

Accepts a float to modify the chance in this step of the calculation.

ID	Name	Function Args	Optional Args	Return Type
1113	MC_PRE_PLANETARIUM_APPLY_ITEMS	(float Chance)	-	float

MC_PRE_PLANETARIUM_APPLY_PLANETARIUM_PENALTY

After ensuring the stage is valid, the game then checks if a planetarium has been entered before. If so, the chance will be locked at 1% (10% with Telescope Lens).

If you're looking to add an item like Telescope Lens which modifies the base chance, have a look at MC_PRE_PLANETARIUM_APPLY_TELESCOPE_LENS instead.

Accepts a boolean. Return false to bypass the planetarium enter penalty.

ID	Name	Function Args	Optional Args	Return Type
1111	MC_PRE_PLANETARIUM_APPLY_PLANETARIUM_PENALTY	void	-	boolean

MC_PRE_PLANETARIUM_APPLY_STAGE_PENALTY

This callback is run at the start of planetarium calculation. Before running calculation, the game first checks if the current floor is valid to spawn a planetarium. If the current floor is invalid, all further calculation (and thus, all further callbacks) will be canceled.

By default, planetariums cannot spawn past Depths II (Womb II with Telescope Lens).

This callback can be used, for example, to add custom planetarium spawn rules on custom floors, or to add new items like Telescope Lens which can augment the rules.

Accepts a boolean. Return false to bypass the planetarium stage penalty.

ID	Name	Function Args	Optional Args	Return Type
1110	MC_PRE_PLANETARIUM_APPLY_STAGE_PENALTY	void	-	boolean

MC_PRE_PLANETARIUM_APPLY_TELESCOPE_LENS

Finally, after checking all of the above, Telescope Lens adds an additional 9% chance to the base chance, bringing the base generation chance to 10%.

Accepts a float to modify the chance in this step of the calculation.

ID	Name	Function Args	Optional Args	Return Type
1114	MC_PRE_PLANETARIUM_APPLY_TELESCOPE_LENS	(float Chance)	-	float

MC_PRE_PLANETARIUM_APPLY_TREASURE_PENALTY

After ensuring planetariums haven't been entered before, the game then checks how many treasure rooms have been entered. If the amount of treasure rooms entered is greater than or equal to the current stage number, the chance will be locked at 1% (10% with Telescope Lens).

If you're looking to add an item like Telescope Lens which modifies the base chance, have a look at MC_PRE_PLANETARIUM_APPLY_TELESCOPE_LENS instead.

Accepts a boolean. Return false to bypass the planetarium treasure room penalty entirely, meaning the game will act as if no treasure rooms have been entered.

Alternatively accepts an int to modify how many treasure rooms the game will believe has been entered.

ID	Name	Function Args	Optional Args	Return Type
1112	MC_PRE_PLANETARIUM_APPLY_TREASURE_PENALTY	(int TreasureRoomsVisited)	-	boolean or int

MC_POST_PLANETARIUM_CALCULATE

This will override all previous calculation values, ultimately dictating the planetarium chance.

Accepts a float to modify the chance.

ID	Name	Function Args	Optional Args	Return Type
1115	MC_POST_PLANETARIUM_CALCULATE	(float Chance)	-	float

MC_PRE_PLAYERHUD_RENDER_ACTIVE_ITEM

Accepts true to cancel rendering.

ID	Name	Function Args	Optional Args	Return Type
1119	MC_PRE_PLAYERHUD_RENDER_ACTIVE_ITEM	(EntityPlayer Player, ActiveSlot Slot, Vector Offset, float Alpha, float Scale, Vector ChargeBarOffset)	-	boolean
### MC_POST_PLAYERHUD_RENDER_ACTIVE_ITEM

ID	Name	Function Args	Optional Args	Return Type
1079	MC_POST_PLAYERHUD_RENDER_ACTIVE_ITEM	(EntityPlayer Player, ActiveSlot Slot, Vector Offset, float Alpha, float Scale, Vector ChargeBarOffset)	-	void

MC_PRE_PLAYERHUD_RENDER_HEARTS

Return true to cancel hearts HUD rendering.

ID	Name	Function Args	Optional Args	Return Type
1118	MC_PRE_PLAYERHUD_RENDER_HEARTS	(Vector Offset(?), Sprite HeartsSprite, Vector Position, float Unknown, EntityPlayer Player)	-	boolean

MC_POST_PLAYERHUD_RENDER_HEARTS

ID	Name	Function Args	Optional Args	Return Type
1091	MC_POST_PLAYERHUD_RENDER_HEARTS	(Vector Offset(?), Sprite HeartsSprite, Vector Position, float Unknown, EntityPlayer Player)	-	void

MC_PRE_PLAYERHUD_TRINKET_RENDER

Accepts returning a table, with any combination of the following fields:

• Position - Alters trinket position.
• Scale - Alters trinket scale.
• CropOffset - Alters the crop on the sprite on its spritesheet. Allows alternate sprites for the same trinket rendered this way, such as Monkey Paw.

Alternative accepts true, which cancels trinket rendering.

ID	Name	Function Args	Optional Args	Return Type
1264	MC_PRE_PLAYERHUD_TRINKET_RENDER	(int Slot, Vector Position, float Scale, EntityPlayer Player, Vector CropOffset)	int Slot	table or boolean

MC_PRE_PLAYER_APPLY_INNATE_COLLECTIBLE_NUM

ID	Name	Function Args	Optional Args	Return Type
1092	MC_PRE_PLAYER_APPLY_INNATE_COLLECTIBLE_NUM	(int ModCount, EntityPlayer Player, CollectibleType Type, boolean OnlyCountTrueItems)	-	int

MC_POST_PLAYER_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1231	MC_POST_PLAYER_COLLISION	(EntityPlayer Player, Entity Collider, boolean Low)	PlayerVariant	void

MC_PLAYER_GET_ACTIVE_MAX_CHARGE

Accepts an integer to change chargebar for the active item.

ID	Name	Function Args	Optional Args	Return Type
1072	MC_PLAYER_GET_ACTIVE_MAX_CHARGE	(CollectibleType Collectible, EntityPlayer Player, int VarData)	CollectibleType	int

MC_PLAYER_GET_ACTIVE_MIN_USABLE_CHARGE

Accepts an integer to change the minimum charge to use the active item. If the item currently has the minimum amount of charge, it'll also show the white outline.

ID	Name	Function Args	Optional Args	Return Type
1073	MC_PLAYER_GET_ACTIVE_MIN_USABLE_CHARGE	(ActiveSlot Slot, EntityPlayer Player)	CollectibleType	int

MC_PLAYER_GET_HEALTH_TYPE

Accepts an HealthType to change health type for the character.

ID	Name	Function Args	Optional Args	Return Type
1067	MC_PLAYER_GET_HEALTH_TYPE	(EntityPlayer Player)	PlayerType	HealthType

MC_PLAYER_GET_HEART_LIMIT

Accepts an override integer for heart limit.

-

You can set the limit to any arbitrary amount but the game can only render up to 4 lines of hearts in the HUD. However, even if they're not visible, the hearts still work properly.

ID	Name	Function Args	Optional Args	Return Type
1074	MC_PLAYER_GET_HEART_LIMIT	(EntityPlayer Player, int HeartLimit, boolean IsKeeper)	PlayerType	int

MC_POST_PLAYER_GET_MULTI_SHOT_PARAMS

Return a MultiShotParams object to change the properties of the players shooting behavior in regards to the MultiShotParams object properties.

ID	Name	Function Args	Optional Args	Return Type
1251	MC_POST_PLAYER_GET_MULTI_SHOT_PARAMS	(EntityPlayer Player)	PlayerType	MultiShotParams

MC_PLAYER_INIT_POST_LEVEL_INIT_STATS

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1042	MC_PLAYER_INIT_POST_LEVEL_INIT_STATS	(EntityPlayer Player)	PlayerType	void

MC_PLAYER_INIT_PRE_LEVEL_INIT_STATS

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1127	MC_PLAYER_INIT_PRE_LEVEL_INIT_STATS	(EntityPlayer Player)	PlayerType	void

MC_POST_PLAYER_NEW_LEVEL

ID	Name	Function Args	Optional Args	Return Type
1078	MC_POST_PLAYER_NEW_LEVEL	(EntityPlayer Player)	PlayerType	void

MC_POST_PLAYER_NEW_ROOM_TEMP_EFFECTS

ID	Name	Function Args	Optional Args	Return Type
1077	MC_POST_PLAYER_NEW_ROOM_TEMP_EFFECTS	(EntityPlayer Player)	PlayerType	void

MC_PRE_PLAYER_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1082	MC_PRE_PLAYER_RENDER	(EntityPlayer Player, Vector Offset)	PlayerVariant	Vector or boolean

MC_PRE_PLAYER_TAKE_DMG

Runs earlier than MC_ENTITY_TAKE_DMG, and even if the player is considered invincible or has Holy Mantles.

Only accepts returning false to cancel the damage. Good for giving the player invincibility that takes precedence over other damage negation effects, such as Holy Mantle.

ID	Name	Function Args	Optional Args	Return Type
1008	MC_PRE_PLAYER_TAKE_DMG	(EntityPlayer Player, float Damage, DamageFlags DamageFlags, EntityRef Source, int DamageCountdown)	PlayerVariant	boolean

MC_PRE_PLAYER_ADD_HEARTS

Runs before Add(...)Hearts functions, allows returning a value to change the given amount of health. Functions that include an argument (e.g. ignoreKeeper for AddMaxHearts) provide the value using OptionalArg.

ID	Name	Function Args	Optional Args	Return Type
1009	MC_PRE_PLAYER_ADD_HEARTS	(EntityPlayer Player, int Amount, AddHealthType AddHealthType, boolean OptionalArg)	AddHealthType	int

MC_POST_PLAYER_ADD_HEARTS

Runs after Add(...)Hearts functions and MC_PRE_PLAYER_ADD_HEARTS callback. Functions that include an argument (e.g. ignoreKeeper for AddMaxHearts) provide the value using OptionalArg.

ID	Name	Function Args	Optional Args	Return Type
1010	MC_POST_PLAYER_ADD_HEARTS	(EntityPlayer Player, int Amount, AddHealthType AddHealthType, boolean OptionalArg)	AddHealthType	void

MC_PRE_PLAYER_TRIGGER_ROOM_CLEAR

Accepts false to cancel trigger effects.

ID	Name	Function Args	Optional Args	Return Type
1069	MC_PRE_PLAYER_TRIGGER_ROOM_CLEAR	(EntityPlayer Player)	PlayerVariant	boolean

MC_PRE_PLAYER_USE_BOMB

Return false to stop the player from using a bomb.

ID	Name	Function Args	Optional Args	Return Type
1020	MC_PRE_PLAYER_USE_BOMB	(EntityPlayer Player)	PlayerVariant	boolean

MC_POST_PLAYER_USE_BOMB

ID	Name	Function Args	Optional Args	Return Type
1021	MC_POST_PLAYER_USE_BOMB	(EntityPlayer Player, EntityBomb Bomb)	PlayerVariant	void

MC_POST_PROJECTILE_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1245	MC_POST_PROJECTILE_COLLISION	(EntityProjectile Projectile, Entity Collider, boolean Low)	ProjectileVariant	void

MC_PRE_PROJECTILE_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1085	MC_PRE_PROJECTILE_RENDER	(EntityProjectile Projectile, Vector Offset)	ProjectileVariant	Vector or boolean

MC_PRE_RENDER_CUSTOM_CHARACTER_MENU

Accepts no return parameters.

Execution informations

This callback only triggers when a custom character is selected, it doesn't trigger on regular characters.

ID	Name	Function Args	Optional Args	Return Type
1333	MC_PRE_RENDER_CUSTOM_CHARACTER_MENU	(PlayerType PlayerType, Vector RenderPos, Sprite DefaultSprite)	PlayerType	void

MC_PRE_RENDER_ENTITY_LIGHTING

Accepts an override Vector for Offset.

Alternatively accepts false to stop the rendering.

ID	Name	Function Args	Optional Args	Return Type
1152	MC_PRE_RENDER_ENTITY_LIGHTING	(Entity Entity, Vector Offset)	EntityType	Vector or boolean

MC_PRE_RENDER_GRID_LIGHTING

Accepts an override Vector for Offset.

Alternatively accepts false to stop the rendering.

ID	Name	Function Args	Optional Args	Return Type
1151	MC_PRE_RENDER_GRID_LIGHTING	(GridEntity GridEntity, Vector Offset)	GridEntityType	Vector or boolean

MC_PRE_RENDER_PLAYER_BODY

Accepts an override vector for RenderPos.

Alternatively accepts a false to stop the rendering.

ID	Name	Function Args	Optional Args	Return Type
1039	MC_PRE_RENDER_PLAYER_BODY	(EntityPlayer player, Vector RenderPos)	PlayerType	Vector or boolean

MC_PRE_RENDER_PLAYER_HEAD

Accepts an override Vector for RenderPos.

Alternatively accepts a false to stop the rendering.

ID	Name	Function Args	Optional Args	Return Type
1038	MC_PRE_RENDER_PLAYER_HEAD	(EntityPlayer player, Vector RenderPos)	PlayerType	Vector or boolean

MC_PRE_RENDER

Gets called right before the Manager::Render() function gets called.

ID	Name	Function Args	Optional Args	Return Type
1135	MC_PRE_RENDER	void	-	void

MC_PRE_REPLACE_SPRITESHEET

Accepts a table of parameters: {int LayerID, string PNGFilename}

ID	Name	Function Args	Optional Args	Return Type
1116	MC_PRE_REPLACE_SPRITESHEET	(int LayerID, string PNGFilename)	string ANM2Filename	table

MC_POST_REPLACE_SPRITESHEET

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1117	MC_POST_REPLACE_SPRITESHEET	(int LayerID, string PNGFilename)	string ANM2Filename	void

MC_PRE_RESTOCK_SHOP

Accepts false to cancel the restock, blocking shop rerolls from restock machines or restocks from Restock altogether.

Partial

This callback is called for both Room::ShopRestockFull and Room::ShopRestockPartial! Partial is provided to distinguish the two.

ID	Name	Function Args	Optional Args	Return Type
1070	MC_PRE_RESTOCK_SHOP	(boolean Partial)	-	void

MC_POST_RESTOCK_SHOP

Accepts no return parameters.

Partial

This callback is called for both Room::ShopRestockFull and Room::ShopRestockPartial! Partial is provided to distinguish the two.

ID	Name	Function Args	Optional Args	Return Type
1071	MC_POST_RESTOCK_SHOP	(boolean Partial)	-	void

MC_PRE_ROOM_EXIT

Accepts no return parameters.

NewLevel

NewLevel returns true when entering a new level or when exiting a run.

ID	Name	Function Args	Optional Args	Return Type
1043	MC_PRE_ROOM_EXIT	(EntityPlayer Player, boolean NewLevel)	-	void

MC_PRE_ROOM_GRID_ENTITY_SPAWN

This is called during Room initiization when GridEntities from the layout are being spawned.

Accepts false to cancel spawning the grid or a table of {Type, Variant, Vardata, SpawnSeed} to modify it.

Warning

This does not fire for random decorations spawned by the game! Use MC_PRE_GRID_ENTITY_SPAWN for these.

ID	Name	Function Args	Optional Args	Return Type
1192	MC_PRE_ROOM_GRID_ENTITY_SPAWN	(GridEntityType Type, int Variant, int VarData, int GridIdx, int SpawnSeed)	GridEntityType Type	boolean or table

MC_PRE_ROOM_TRIGGER_CLEAR

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1068	MC_PRE_ROOM_TRIGGER_CLEAR	(boolean PlaySound)	-	void

MC_POST_SAVESLOT_LOAD

This is called wheenver a saveslot is loaded by the game.

This is the callback you should use to handle savedata loads, ideally, from normal Mod::LoadData to Repentogon Marks/Achievement checks, since it's the callback that triggers when those are loaded.

The first parameter is the slot you should care about, the 2nd parameter (isslotselected) indicates if the slot that is being loaded has actually been selected from the save menu screen (you can limit your save handling to when this is true if you want to get fancy), and the 3rd parameter(rawslot) is the actual saveslot the game uses (not the one the api uses since it can be 0!).

Warning

This callback is called many times before a run is started, either from changing saveslots naturally or because the game doesnt give a damn, so code accounting for that, clearing previous data when necessary. The 3rd param is actually only useful to check for the 0 slot state, which is the one the game defaults to before the actual slot is loaded by the player. When on this state, the moddata and the gamedata WONT BE IN SYNC (moddata is slot 1, while vanilla game data is 3)

ID	Name	Function Args	Optional Args	Return Type
1470	MC_POST_SAVESLOT_LOAD	(int saveslot, boolean isslotselected, int rawslot)

MC_PRE_SFX_PLAY

Accepts a table of parameters: {ID, Volume, FrameDelay, Loop, Pitch, Pan}

Alternatively accepts false to cancel the sound.

Example Code

This code will forcibly loop every sound (for better or worse).

function mod:myFunction(ID, Volume, FrameDelay, Loop, Pitch, Pan)
    return {ID, Volume, FrameDelay, true, Pitch, Pan}
end
mod:AddCallback(ModCallbacks.MC_PRE_SFX_PLAY, mod.myFunction)

ID	Name	Function Args	Optional Args	Return Type
1030	MC_PRE_SFX_PLAY	(int ID, float Volume, int FrameDelay, boolean Loop, float Pitch, float Pan)	SoundEffect	table or boolean

MC_POST_SFX_PLAY

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1031	MC_POST_SFX_PLAY	(int ID, float Volume, int FrameDelay, boolean Loop, float Pitch, float Pan)	SoundEffect	void

MC_PRE_SLOT_COLLISION

Just like the collision callbacks in the vanilla API, the Low value is true if the entity collided with the collider first, and false if the opposite is true.

Return true to ignore collision, false to collide but not execute internal code.

Also accepts returning a table, with any combination of the following fields:

• Collide: Set to true to force the entities to physically collide (push each other away), unless the "Collider" ignores the collision. Set to false to ignore the physical collision without necessarily skipping on-collision effects.
• SkipCollisionEffects: Set to true to skip the on-collision code of this entity. Does not affect the physical collision. Won't skip the on-collision code of the "Collider".

ID	Name	Function Args	Optional Args	Return Type
1240	MC_PRE_SLOT_COLLISION	(EntitySlot, Entity Collider, boolean Low)	SlotVariant	boolean

MC_POST_SLOT_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1241	MC_POST_SLOT_COLLISION	(EntitySlot, Entity Collider, boolean Low)	SlotVariant	void

MC_PRE_SLOT_CREATE_EXPLOSION_DROPS

Return false to stop explosions from dropping the standard consumables. This is useful, for example, to allow custom slots to drop their own loot on explosion.

ID	Name	Function Args	Optional Args	Return Type
1123	MC_PRE_SLOT_CREATE_EXPLOSION_DROPS	(EntitySlot)	SlotVariant	boolean

MC_POST_SLOT_CREATE_EXPLOSION_DROPS

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1124	MC_POST_SLOT_CREATE_EXPLOSION_DROPS	(EntitySlot)	SlotVariant	void

MC_POST_SLOT_INIT

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1121	MC_POST_SLOT_INIT	(EntitySlot)	SlotVariant	void

MC_PRE_SLOT_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1089	MC_PRE_SLOT_RENDER	(EntitySlot Slot, Vector Offset)	SlotVariant	Vector or boolean

MC_POST_SLOT_RENDER

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1090	MC_POST_SLOT_RENDER	(EntitySlot Slot, Vector Offset)	SlotVariant	void

MC_PRE_SLOT_SET_PRIZE_COLLECTIBLE

Used by Shell Game, Hell Game, and Crane Game.

Accepts a CollectibleType to override what the game will pay out with.

ID	Name	Function Args	Optional Args	Return Type
1125	MC_PRE_SLOT_SET_PRIZE_COLLECTIBLE	(EntitySlot, CollectibleType Type)	SlotVariant	CollectibleType

MC_POST_SLOT_SET_PRIZE_COLLECTIBLE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1126	MC_POST_SLOT_SET_PRIZE_COLLECTIBLE	(EntitySlot, CollectibleType Type)	SlotVariant	void

MC_PRE_SLOT_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1169	MC_PRE_SLOT_UPDATE	(EntitySlot Slot)	SlotVariant	boolean

MC_POST_SLOT_UPDATE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1122	MC_POST_SLOT_UPDATE	(EntitySlot)	SlotVariant	void

MC_POST_TEAR_COLLISION

Runs after the on-collision code of this entity, assuming it wasn't skipped.

ID	Name	Function Args	Optional Args	Return Type
1233	MC_POST_TEAR_COLLISION	(EntityTear Tear, Entity Collider, boolean Low)	TearVariant	void

MC_PRE_TEAR_RENDER

Accepts a Vector to modify render offset

Alternatively accepts false to cancel rendering

Shadows

Canceling this callback will not stop rendering of entity shadows. This is being investigated, but in the meantime call SetShadowSize(0) on the entity in MC_POST_UPDATE.

ID	Name	Function Args	Optional Args	Return Type
1084	MC_PRE_TEAR_RENDER	(EntityTear Tear, Vector Offset)	TearVariant	Vector or boolean

MC_POST_TRIGGER_COLLECTIBLE_REMOVED

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1095	MC_POST_TRIGGER_COLLECTIBLE_REMOVED	(EntityPlayer Player, CollectibleType Type)	CollectibleType	void

MC_PRE_TRIGGER_PLAYER_DEATH

Fires right before the game over screen, but BEFORE the game checks for vanilla revive effects like 1UP.

Return false or call player:Revive() to cancel the death, reviving the player in-place with half a heart. This will also prevent later callbacks from running.

Warning

Returning false or calling player:Revive() may remove the current run's ability to save. This occurs because the game immediately deletes the save file during the death animation if there's no pending revives, and this callback doesn't fire fast enough to register a revive on death as it occurs right before the game over screen.

In order to prevent this, only attempt to revive the player if they have an item or effect with REPENTOGON's "revive" customtag, which allows the item/effect to count as an extra life on the HUD and prevents the game from deleting the run save upon player death. See the page on items.xml for more information and some example XML/code.

ID	Name	Function Args	Optional Args	Return Type
1050	MC_PRE_TRIGGER_PLAYER_DEATH	(EntityPlayer Player)	-	boolean

MC_TRIGGER_PLAYER_DEATH_POST_CHECK_REVIVES

Fires right before the game over screen, but AFTER the game checks for vanilla revive effects like 1UP.

Return false or call player:Revive() to cancel the death, reviving the player in-place with half a heart. This will also prevent later callbacks from running.

Warning

Returning false or calling player:Revive() may remove the current run's ability to save. This occurs because the game immediately deletes the save file during the death animation if there's no pending revives, and this callback doesn't fire fast enough to register a revive on death as it occurs right before the game over screen.

In order to prevent this, only attempt to revive the player if they have an item or effect with REPENTOGON's "revive" customtag, which allows the item/effect to count as an extra life on the HUD and prevents the game from deleting the run save upon player death. See the page on items.xml for more information and some example XML/code.

ID	Name	Function Args	Optional Args	Return Type
1051	MC_TRIGGER_PLAYER_DEATH_POST_CHECK_REVIVES	(EntityPlayer Player)	-	boolean

MC_PRE_PLAYER_REVIVE

Called before the player revives.

Return false to cancel it."

ID	Name	Function Args	Optional Args	Return Type
1481	MC_PRE_PLAYER_REVIVE	(EntityPlayer Player)	-	boolean

MC_POST_PLAYER_REVIVE

Called after the player revives, assuming it wasn't cancelled.

ID	Name	Function Args	Optional Args	Return Type
1482	MC_POST_PLAYER_REVIVE	(EntityPlayer Player)	-	void

MC_POST_TRIGGER_TRINKET_ADDED

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1096	MC_POST_TRIGGER_TRINKET_ADDED	(EntityPlayer Player, TrinketType Type, boolean FirstTimePickingUp)	TrinketType	void

MC_POST_TRIGGER_TRINKET_REMOVED

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1097	MC_POST_TRIGGER_TRINKET_REMOVED	(EntityPlayer Player, TrinketType Type)	TrinketType	void

MC_POST_TRIGGER_WEAPON_FIRED

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1098	MC_POST_TRIGGER_WEAPON_FIRED	(Vector FireDirection, int FireAmount, Entity Owner, Weapon Weapon)	WeaponType	void

MC_PRE_USE_CARD

Accepts true to cancel card use.

ID	Name	Function Args	Optional Args	Return Type
1064	MC_PRE_USE_CARD	(Card ID, EntityPlayer Player, int UseFlag)	-	boolean

MC_PRE_USE_PILL

Accepts true to cancel pill use.

ID	Name	Function Args	Optional Args	Return Type
1065	MC_PRE_USE_PILL	(PillEffect ID, PillColor PillColor, EntityPlayer Player, int UseFlag)	-	boolean

MC_POST_WEAPON_FIRE

Accepts no return parameters.

ID	Name	Function Args	Optional Args	Return Type
1105	MC_POST_WEAPON_FIRE	(Weapon Weapon, Vector FireDirection, boolean IsShooting, boolean IsInterpolated)	WeaponType	void

MC_PRE_PICKUP_GET_LOOT_LIST

Called before the pickup determines its loot content. Accepts a LootList to change loot content.

ID	Name	Function Args	Optional Args	Return Type
1333	MC_PRE_PICKUP_GET_LOOT_LIST	(EntityPickup Pickup, boolean ShouldAdvance)	PickupVariant	void

MC_PRE_PICKUP_UPDATE_GHOST_PICKUPS

Called before a ghost pickup of the loot content is applied to the pickup. Return true to apply pickup ghost to your pickup entity, false to cancel it.

ID	Name	Function Args	Optional Args	Return Type
1334	MC_PRE_PICKUP_UPDATE_GHOST_PICKUPS	(EntityPickup Pickup)	PickupVariant	boolean

MC_POST_PLAYER_TRIGGER_EFFECT_REMOVED

Called after the player's ItemConfigItem TemporaryEffect is removed

ID	Name	Function Args	Optional Args	Return Type
1268	MC_POST_PLAYER_TRIGGER_EFFECT_REMOVED	(EntityPlayer Player, [ItemConfigItem][../ItemConfig_Item.md])	[ItemConfigItem][../ItemConfig_Item.md]	void

MC_POST_ROOM_TRIGGER_EFFECT_REMOVED

Called after the room's TemporaryEffects is removed.

Room has its own TemporaryEffects that are accessed through Room::GetEffects()

ID	Name	Function Args	Optional Args	Return Type
1269	MC_POST_ROOM_TRIGGER_EFFECT_REMOVED	([ItemConfigItem][../ItemConfig_Item.md])	[ItemConfigItem][../ItemConfig_Item.md]	void

MC_PRE_PLAYER_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1171	MC_PRE_PLAYER_GRID_COLLISION	(EntityPlayer Player, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PLAYER_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1172	MC_PLAYER_GRID_COLLISION	(EntityPlayer Player, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_TEAR_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1173	MC_PRE_TEAR_GRID_COLLISION	(EntityTear Tear, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_TEAR_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1174	MC_TEAR_GRID_COLLISION	(EntityTear Tear, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_FAMILIAR_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1175	MC_PRE_FAMILIAR_GRID_COLLISION	(EntityFamiliar Familiar, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_FAMILIAR_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1176	MC_FAMILIAR_GRID_COLLISION	(EntityFamiliar Familiar, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_BOMB_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1177	MC_PRE_BOMB_GRID_COLLISION	(EntityBomb Bomb, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_BOMB_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1178	MC_BOMB_GRID_COLLISION	(EntityBomb Bomb, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_PICKUP_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1179	MC_PRE_PICKUP_GRID_COLLISION	(EntityPickup Pickup, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PICKUP_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1180	MC_PICKUP_GRID_COLLISION	(EntityPickup Pickup, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_PROJECTILE_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1181	MC_PRE_PROJECTILE_GRID_COLLISION	(EntityProjectile Projectile, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PROJECTILE_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1182	MC_PROJECTILE_GRID_COLLISION	(EntityProjectile Projectile, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_PRE_NPC_GRID_COLLISION

Called before this entity collides with the GridEntity.

Return true to ignore collision.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1183	MC_PRE_NPC_GRID_COLLISION	(EntityNPC NPC, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_NPC_GRID_COLLISION

Called when this entity collides with the GridEntity, assuming it wasn't skipped.

Warning

GridEntity can also be nil, as this callback counts empty ground as a grid entity.

ID	Name	Function Args	Optional Args	Return Type
1184	MC_NPC_GRID_COLLISION	(EntityNPC NPC, int GridIndex, GridEntity GridEntity)	GridEntityType	boolean

MC_POST_PROJECTILE_DEATH

ID	Name	Function Args	Optional Args	Return Type
1032	MC_POST_PROJECTILE_DEATH	(EntityProjectile Projectile)	ProjectileVariant	boolean

MC_POST_TEAR_DEATH

ID	Name	Function Args	Optional Args	Return Type
1032	MC_POST_TEAR_DEATH	(EntityTear Tear)	TearVariant	boolean

MC_POST_BOSS_INTRO_SHOW

Accepts no return parameters.

Called right after the boss intro is initialized. BossID2 is for Double Trouble.

ID	Name	Function Args	Optional Args	Return Type
1270	MC_POST_BOSS_INTRO_SHOW	(BossType BossID1, BossType BossID2)	-	void

MC_POST_ROOM_TRANSITION_UPDATE

ID	Name	Function Args	Optional Args	Return Type
1271	MC_POST_ROOM_TRANSITION_UPDATE	void	-	void

MC_POST_ROOM_TRANSITION_RENDER

ID	Name	Function Args	Optional Args	Return Type
1272	MC_POST_ROOM_TRANSITION_RENDER	void	-	void

MC_PRE_PLAYER_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1160	MC_PRE_PLAYER_UPDATE	(EntityPlayer Player)	PlayerVariant	boolean

MC_PRE_TEAR_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1161	MC_PRE_TEAR_UPDATE	(EntityTear Tear)	TearVariant	boolean

MC_PRE_FAMILIAR_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1162	MC_PRE_FAMILIAR_UPDATE	(EntityFamiliar Familiar)	FamiliarVariant	boolean

MC_PRE_BOMB_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1163	MC_PRE_BOMB_UPDATE	(EntityBomb Bomb)	BombVariant	boolean

MC_PRE_PICKUP_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1164	MC_PRE_PICKUP_UPDATE	(EntityPickup Pickup)	PickupVariant	boolean

MC_PRE_KNIFE_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1165	MC_PRE_KNIFE_UPDATE	(EntityKnife Knife)	KnifeSubType	boolean

MC_PRE_PROJECTILE_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1166	MC_PRE_PROJECTILE_UPDATE	(EntityProjectile Projectile)	ProjectileVariant	boolean

MC_PRE_LASER_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1167	MC_PRE_LASER_UPDATE	(EntityLaser Laser)	LaserVariant	boolean

MC_PRE_EFFECT_UPDATE

Called before this entity is updated.

Return true if the internal AI should be ignored, false or nil/nothing otherwise.

ID	Name	Function Args	Optional Args	Return Type
1168	MC_PRE_EFFECT_UPDATE	(EntityEffect Effect)	EffectVariant	boolean