生物群系修改器

生物群系修改器是一种数据驱动系统，可以修改生物群系的许多方面，包括添加或移除 PlacedFeature、添加或移除生物生成、改变气候，以及调整植被和水的颜色。NeoForge 提供若干默认修改器，覆盖玩家和 Mod 开发者的大多数需求。

推荐阅读

• 玩家或整合包开发者：阅读应用修改器和内置修改器。
• 只需简单增删内容的 Mod 开发者：再阅读数据生成。
• 需要自定义或复杂修改的开发者：阅读应用修改器、创建自定义修改器和数据生成。

应用生物群系修改器

要让 NeoForge 加载修改器 JSON，文件必须位于 Mod 资源或数据包的 data/<modid>/neoforge/biome_modifier/<path>.json。NeoForge 加载后会读取指令，在世界载入时将修改应用到所有目标生物群系。数据包可通过同路径、同名称的新 JSON 覆盖 Mod 的已有修改器。

可参考内置修改器手动编写 JSON，也可按数据生成一节生成。

内置生物群系修改器

以下类型由 NeoForge 注册，任何人均可使用。

不执行操作

此修改器不执行任何修改。整合包作者和玩家可用下面的 JSON 覆盖 Mod 的对应文件，从而禁用其修改器。

JSON

{
    "type": "neoforge:none"
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> NO_OP_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "no_op_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Register the biome modifiers.
    bootstrap.register(NO_OP_EXAMPLE, NoneBiomeModifier.INSTANCE);
});

添加地物

此类型向生物群系添加 PlacedFeature（例如树木、矿石），使其在世界生成时出现。参数包括目标生物群系 ID 或标签、待添加地物 ID 或标签，以及地物生成所属的 GenerationStep.Decoration。

JSON

{
    "type": "neoforge:add_features",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:your_biome_tag",
    // Can either be a placed feature id, such as "examplemod:add_features_example",
    // or a list of placed feature ids, such as ["examplemod:add_features_example", minecraft:ice_spike", ...],
    // or a placed feature tag, such as "#examplemod:placed_feature_tag".
    "features": "namespace:your_feature",
    // See the GenerationStep.Decoration enum in code for a list of valid enum names.
    // The decoration step section further down also has the list of values for reference.
    "step": "underground_ores"
}

数据生成

// Assume we have some PlacedFeature named EXAMPLE_PLACED_FEATURE.
// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> ADD_FEATURES_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "add_features_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<PlacedFeature> placedFeatures = bootstrap.lookup(Registries.PLACED_FEATURE);

    // Register the biome modifiers.
    bootstrap.register(ADD_FEATURES_EXAMPLE,
        new AddFeaturesBiomeModifier(
            // The biome(s) to generate within
            HolderSet.direct(biomes.getOrThrow(Biomes.PLAINS)),
            // The feature(s) to generate within the biomes
            HolderSet.direct(placedFeatures.getOrThrow(EXAMPLE_PLACED_FEATURE)),
            // The generation step
            GenerationStep.Decoration.LOCAL_MODIFICATIONS
        )
    );
})

警告 向生物群系添加原版 PlacedFeature 时要谨慎，可能触发地物循环顺序冲突：两个生物群系在同一个 GenerationStep 中都有相同两个地物，但顺序相反，从而导致崩溃。出于相似原因，不应在多个修改器中复用同一个 PlacedFeature。

原版地物可以在生物群系 JSON 中引用，也可通过修改器添加，但不应同时使用两种方式。如果确实需要这样添加，最简单的规避方式是在自己的命名空间下复制原版地物。

移除地物

此类型从生物群系移除树木、矿石等地物，使其不再随世界生成。参数包括目标生物群系 ID 或标签、待移除 PlacedFeature 的 ID 或标签，以及要移除的 GenerationStep.Decoration 阶段。

JSON

{
    "type": "neoforge:remove_features",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:your_biome_tag",
    // Can either be a placed feature id, such as "examplemod:add_features_example",
    // or a list of placed feature ids, such as ["examplemod:add_features_example", "minecraft:ice_spike", ...],
    // or a placed feature tag, such as "#examplemod:placed_feature_tag".
    "features": "namespace:problematic_feature",
    // Optional field specifying a GenerationStep, or a list of GenerationSteps, to remove features from.
    // If omitted, defaults to all GenerationSteps.
    // See the GenerationStep.Decoration enum in code for a list of valid enum names.
    // The decoration step section further down also has the list of values for reference.
    "steps": ["underground_ores", "underground_decoration"]
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> REMOVE_FEATURES_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "remove_features_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<PlacedFeature> placedFeatures = bootstrap.lookup(Registries.PLACED_FEATURE);

    // Register the biome modifiers.
    bootstrap.register(REMOVE_FEATURES_EXAMPLE,
        new RemoveFeaturesBiomeModifier(
            // The biome(s) to remove from
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            // The feature(s) to remove from the biomes
            HolderSet.direct(placedFeatures.getOrThrow(OrePlacements.ORE_DIAMOND)),
            // The generation steps to remove from
            Set.of(
                GenerationStep.Decoration.LOCAL_MODIFICATIONS,
                GenerationStep.Decoration.UNDERGROUND_ORES
            )
        )
    );
});

添加生物生成

此类型向生物群系添加实体生成。参数包括目标生物群系 ID 或标签，以及待添加实体的 SpawnerData。每项数据包含实体 ID、生成权重，以及一次生成的最小和最大数量。

提示 添加新实体时，务必通过 RegisterSpawnPlacementsEvent 注册生成限制，让实体安全地生成在地面或水中。否则实体可能在半空出现，随后坠落。

JSON

{
    "type": "neoforge:add_spawns",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:biome_tag",
    // Can be either a single object or a list of objects.
    "spawners": [
        {
            "type": "namespace:entity_type", // The id of the entity type to spawn
            "weight": 100, // int, spawn weight
            "minCount": 1, // int, minimum group size
            "maxCount": 4 // int, maximum group size
        },
        {
            "type": "minecraft:ghast",
            "weight": 1,
            "minCount": 5,
            "maxCount": 10
        }
    ]
}

数据生成

// Assume we have some EntityType<?> named EXAMPLE_ENTITY.
// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> ADD_SPAWNS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "add_spawns_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);

    // Register the biome modifiers.
    bootstrap.register(ADD_SPAWNS_EXAMPLE,
        new AddSpawnsBiomeModifier(
            // The biome(s) to spawn the mobs within
            HolderSet.direct(biomes.getOrThrow(Biomes.PLAINS)),
            // The spawners of the entities to add
            List.of(
                new SpawnerData(EXAMPLE_ENTITY, 100, 1, 4),
                new SpawnerData(EntityType.GHAST, 1, 5, 10)
            )
        )
    );
});

移除生物生成

此类型从生物群系移除实体生成。参数包括目标生物群系 ID 或标签，以及要移除的 EntityType ID 或标签。

JSON

{
    "type": "neoforge:remove_spawns",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:biome_tag",
    // Can either be an entity type id, such as "minecraft:ghast",
    // or a list of entity type ids, such as ["minecraft:ghast", "minecraft:skeleton", ...],
    // or an entity type tag, such as "#minecraft:skeletons".
    "entity_types": "#namespace:entitytype_tag"
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> REMOVE_SPAWNS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "remove_spawns_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<EntityType<?>> entities = bootstrap.lookup(Registries.ENTITY_TYPE);

    // Register the biome modifiers.
    bootstrap.register(REMOVE_SPAWNS_EXAMPLE,
        new RemoveSpawnsBiomeModifier(
            // The biome(s) to remove the spawns from
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            // The entities to remove spawns for
            entities.getOrThrow(EntityTypeTags.SKELETONS)
        )
    );
});

添加生成成本

生成成本是一种较新的机制，让生物在群系内分散生成，减少聚集。每个实体向周围发出 charge，并与其他实体的 charge 叠加。生成新实体时，算法寻找一个位置，要求该处总 charge 场乘以新实体的 charge，小于新实体的 energy_budget。这是较高级的生成方式，可参考最典型使用者灵魂沙峡谷的现有数值。

参数包括目标生物群系 ID 或标签、要添加成本的实体类型 ID 或标签，以及 MobSpawnSettings.MobSpawnCost。后者包含能量预算，结合每个实体的 charge 决定某位置可生成的最大实体数量。

提示 添加新实体时，务必通过 RegisterSpawnPlacementsEvent 注册生成限制。

JSON

{
    "type": "neoforge:add_spawn_costs",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:biome_tag",
    // Can either be an entity type id, such as "minecraft:ghast",
    // or a list of entity type ids, such as ["minecraft:ghast", "minecraft:skeleton", ...],
    // or an entity type tag, such as "#minecraft:skeletons".
    "entity_types": "#minecraft:skeletons",
    "spawn_cost": {
        // The energy budget
        "energy_budget": 1.0,
        // The amount of charge each entity takes up from the budget
        "charge": 0.1
    }
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> ADD_SPAWN_COSTS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "add_spawn_costs_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<EntityType<?>> entities = bootstrap.lookup(Registries.ENTITY_TYPE);

    // Register the biome modifiers.
    bootstrap.register(ADD_SPAWN_COSTS_EXAMPLE,
        new AddSpawnCostsBiomeModifier(
            // The biome(s) to add the spawn costs to
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            // The entities to add the spawn costs for
            entities.getOrThrow(EntityTypeTags.SKELETONS),
            new MobSpawnSettings.MobSpawnCost(
                1.0, // The energy budget
                0.1  // The amount of charge each entity takes up from the budget
            )
        )
    );
});

移除生成成本

此类型从群系移除生成成本，也就是用于分散生物、减少聚集的机制。参数包括目标生物群系 ID 或标签，以及要移除成本的实体类型 ID 或标签。

JSON

{
    "type": "neoforge:remove_spawn_costs",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "#namespace:biome_tag",
    // Can either be an entity type id, such as "minecraft:ghast",
    // or a list of entity type ids, such as ["minecraft:ghast", "minecraft:skeleton", ...],
    // or an entity type tag, such as "#minecraft:skeletons".
    "entity_types": "#minecraft:skeletons"
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> REMOVE_SPAWN_COSTS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "remove_spawn_costs_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<EntityType<?>> entities = bootstrap.lookup(Registries.ENTITY_TYPE);

    // Register the biome modifiers.
    bootstrap.register(REMOVE_SPAWN_COSTS_EXAMPLE,
        new RemoveSpawnCostsBiomeModifier(
            // The biome(s) to remove the spawn costs from
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            // The entities to remove spawn costs for
            entities.getOrThrow(EntityTypeTags.SKELETONS)
        )
    );
});

添加旧式雕刻器

此类型向群系添加雕刻器洞穴和峡谷，即洞穴与山崖更新前使用的洞穴生成方式。它不能添加噪声洞穴，因为后者属于特定的噪声区块生成器系统，并不与生物群系直接绑定。

JSON

    {
    "type": "neoforge:add_carvers",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "minecraft:plains",
    // Can either be a carver id, such as "examplemod:add_carvers_example",
    // or a list of carver ids, such as ["examplemod:add_carvers_example", "minecraft:canyon", ...],
    // or a carver tag, such as "#examplemod:configured_carver_tag".
    "carvers": "examplemod:add_carvers_example",
    // See GenerationStep.Carving in code for a list of valid enum names.
    // Only "air" and "liquid" are available.
    "step": "air"
}

数据生成

// Assume we have some ConfiguredWorldCarver named EXAMPLE_CARVER.
// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> ADD_CARVERS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "add_carvers_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<ConfiguredWorldCarver<?>> carvers = bootstrap.lookup(Registries.CONFIGURED_CARVER);

    // Register the biome modifiers.
    bootstrap.register(ADD_CARVERS_EXAMPLE,
        new AddCarversBiomeModifier(
            // The biome(s) to generate within
            HolderSet.direct(biomes.getOrThrow(Biomes.PLAINS)),
            // The carver(s) to generate within the biomes
            HolderSet.direct(carvers.getOrThrow(EXAMPLE_CARVER)),
            // The generation step
            GenerationStep.Carving.AIR
        )
    );
});

移除旧式雕刻器

此类型从群系移除旧式雕刻器洞穴和峡谷。它不能移除噪声洞穴，因为后者已整合在维度的噪声设置系统中，并不与群系直接绑定。

JSON

{
    "type": "neoforge:remove_carvers",
    // Can either be a biome id, such as "minecraft:plains",
    // or a list of biome ids, such as ["minecraft:plains", "minecraft:badlands", ...],
    // or a biome tag, such as "#c:is_overworld".
    "biomes": "minecraft:plains",
    // Can either be a carver id, such as "examplemod:add_carvers_example",
    // or a list of carver ids, such as ["examplemod:add_carvers_example", "minecraft:canyon", ...],
    // or a carver tag, such as "#examplemod:configured_carver_tag".
    "carvers": "examplemod:add_carvers_example",
    // Can either be a single generation step, such as "air",
    // or a list of generation steps, such as ["air", "liquid"].
    // See GenerationStep.Carving for a list of valid enum names.
    // Only "air" and "liquid" are available.
    "steps": [
        "air",
        "liquid"
    ]
}

数据生成

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> REMOVE_CARVERS_EXAMPLE = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "remove_carvers_example") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);
    HolderGetter<ConfiguredWorldCarver<?>> carvers = bootstrap.lookup(Registries.CONFIGURED_CARVER);

    // Register the biome modifiers.
    bootstrap.register(REMOVE_CARVERS_EXAMPLE,
        new AddFeaturesBiomeModifier(
            // The biome(s) to remove from
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            // The carver(s) to remove from the biomes
            HolderSet.direct(carvers.getOrThrow(Carvers.CAVE)),
            // The generation steps to remove from
            Set.of(
                GenerationStep.Carving.AIR,
                GenerationStep.Carving.LIQUID
            )
        )
    );
});

装饰阶段的可用值

前述 JSON 中的 step 或 steps 对应 GenerationStep.Decoration 枚举。下表按游戏实际生成顺序列出，应把地物放在最合适的阶段。

创建自定义生物群系修改器

BiomeModifier 实现

修改器内部由三部分组成：

• 通过数据包注册的 BiomeModifier，修改群系构建器。
• 通过静态注册的 MapCodec，负责修改器的编解码。
• 用于构造修改器的 JSON，以 MapCodec 的注册 ID 作为可查找类型。

BiomeModifier 有 #modify 和 #codec 两个方法。modify 接受当前群系的 Holder、当前 BiomeModifier.Phase 和待修改群系构建器。每个修改器在每个阶段调用一次，以安排修改时机：

所有修改器都有 type 键，引用所用 MapCodec 的 ID。codec 方法提供编解码修改器的 MapCodec。此 codec 需静态注册，其 ID 就是修改器的 type。

public record ExampleBiomeModifier(HolderSet<Biome> biomes, int value) implements BiomeModifier {
    
    @Override
    public void modify(Holder<Biome> biome, Phase phase, ModifiableBiomeInfo.BiomeInfo.Builder builder) {
        if (phase == /* Pick the phase that best matches what your want to modify */) {
            // Modify the 'builder', checking any information about the biome itself
        }
    }

    @Override
    public MapCodec<? extends BiomeModifier> codec() {
        return EXAMPLE_BIOME_MODIFIER.get();
    }
}

// In some registration class
private static final DeferredRegister<MapCodec<? extends BiomeModifier>> BIOME_MODIFIERS =
    DeferredRegister.create(NeoForgeRegistries.Keys.BIOME_MODIFIER_SERIALIZERS, MOD_ID);

public static final Supplier<MapCodec<ExampleBiomeModifier>> EXAMPLE_BIOME_MODIFIER =
    BIOME_MODIFIERS.register("example_biome_modifier", () -> RecordCodecBuilder.mapCodec(instance ->
        instance.group(
            Biome.LIST_CODEC.fieldOf("biomes").forGetter(ExampleBiomeModifier::biomes),
            Codec.INT.fieldOf("value").forGetter(ExampleBiomeModifier::value)
        ).apply(instance, ExampleBiomeModifier::new)
    ));

生物群系修改器的数据生成

把 RegistrySetBuilder 传给 DatapackBuiltinEntriesProvider，即可通过数据生成创建 JSON，输出位置为 data/<modid>/neoforge/biome_modifier/<path>.json。

关于这两个类的更多信息，见数据包注册表的数据生成。

// Define the ResourceKey for our BiomeModifier.
public static final ResourceKey<BiomeModifier> EXAMPLE_MODIFIER = ResourceKey.create(
    NeoForgeRegistries.Keys.BIOME_MODIFIERS, // The registry this key is for
    ResourceLocation.fromNamespaceAndPath(MOD_ID, "example_modifier") // The registry name
);

// BUILDER is a RegistrySetBuilder passed to DatapackBuiltinEntriesProvider
// in a listener for GatherDataEvent.
BUILDER.add(NeoForgeRegistries.Keys.BIOME_MODIFIERS, bootstrap -> {
    // Lookup any necessary registries.
    // Static registries only need to be looked up if you need to grab the tag data.
    HolderGetter<Biome> biomes = bootstrap.lookup(Registries.BIOME);

    // Register the biome modifiers.
    bootstrap.register(EXAMPLE_MODIFIER,
        new ExampleBiomeModifier(
            biomes.getOrThrow(Tags.Biomes.IS_OVERWORLD),
            20
        )
    );
});

随后会生成以下 JSON：

// In data/examplemod/neoforge/biome_modifier/example_modifier.json
{
    // The registy key of the MapCodec for the modifier
    "type": "examplemod:example_biome_modifier",
    // All additional settings are applied to the root object
    "biomes": "#c:is_overworld",
    "value": 20
}

来源： NeoForged/Documentation（1.21.1）。中文翻译依据提交 4a680cdd4d15。