Convertibles

The main article about vampiric creatures is in the vampiric creatures wiki page.

By default only some vanilla animals can be turned into a vampiric version. You can make any other (vanilla or modded) creature convertible from a data pack by adding it to the vampirism:entity_converter data map.

JSON Schema

schemas/entity_converter.schema.json

Requirements

A creature is only convertible when both of these are set for its entity type:

1. an entity blood value greater than 0, and
2. an entity_converter entry (this page).

Location

data/<namespace>/data_maps/entity_type/entity_converter.json

Data map vampirism:entity_converter, synced to the client. Uses the standard NeoForge data map wrapper (replace / values / remove); values maps an entity type id (or #tag) to an entry.

data/vampirism/data_maps/entity_type/entity_converter.json

{
  "values": {
    "minecraft:cow": {
      "handler": { "type": "vampirism:special", "converted_type": "vampirism:converted_cow" }
    },
    "examplemod:deer": {
      "handler": { "type": "vampirism:default" }
    }
  }
}

Field	Required	Type	Description
handler	no	Converter	How this creature converts. Defaults to vampirism:default with the default attribute modifiers.

Migration

Older versions accepted an overlay field on the entry. It has been removed – the overlay texture is now resolved by convention (see Overlay texture).

Converters

handler is a typed object dispatched on type, registered in the vampirism:converting_handler registry. Add-on mods can register more types.

vampirism:default

Wraps the original creature in a generic converted-creature entity. The original model is reused with a vampire overlay layer, so source-entity interactions (riding, inventories, breeding, …) are not available on the converted creature.

{
  "type": "vampirism:default",
  "attribute_helper": [ /* optional, see below */ ]
}

Field	Required	Type	Description
attribute_helper	no	Attribute modifier[]	Overrides the default attribute scaling.

vampirism:special

Converts the creature into a dedicated converted entity type that keeps full functionality (e.g. a vampire horse you can still ride). Requires that converted entity type to be registered by a mod.

{
  "type": "vampirism:special",
  "converted_type": "vampirism:converted_horse",
  "attribute_helper": [ /* optional */ ]
}

Field	Required	Type	Description
converted_type	yes	Resource location	Entity type to spawn as the converted creature.
attribute_helper	no	Attribute modifier[]	Overrides the default attribute scaling.

Attribute modifiers

When attribute_helper is omitted, the converted creature gets these multipliers:

Attribute	Multiplier
minecraft:attack_damage	×1.3
minecraft:knockback_resistance	×1.3
minecraft:max_health	×1.5
minecraft:movement_speed	×1.2

Providing attribute_helper replaces the entire default list, so re-declare any multiplier you want to keep. Each entry:

{
  "attribute": "minecraft:attack_damage",
  "modifier": 1.3,
  "fallback_base": 2.0
}

Field	Required	Type	Description
attribute	yes	Resource location	The attribute to scale.
modifier	yes	Float provider	Multiplier applied to the base value. A bare number is a constant; an object rolls a random value per conversion.
fallback_base	no	number (default 1.0)	Base value assumed when the source entity type does not define the attribute.

The converted base value is entity_type_base_value × modifier.

Overlay texture

For vampirism:default conversions, the vampire overlay is a client resource looked up by convention:

assets/<source_entity_namespace>/textures/entity/overlay/<source_entity_path>.png

e.g. examplemod:deer needs assets/examplemod/textures/entity/overlay/deer.png. Ship it in a resource pack (or your mod's assets). vampirism:special converters use their own entity's model and texture instead.