Biomes

LCE’s biome system controls terrain surface materials, vegetation, mob spawning, climate properties, and how things look (grass/foliage/water/sky colors). The code lives mainly in Minecraft.World/, with the base class in Biome.h/Biome.cpp and subclasses for each biome variant.

Architecture overview

Biome (base class)
├── BiomeSource          - selects biomes for world coordinates via Layer pipeline
│   └── FixedBiomeSource - returns a single biome everywhere (superflat worlds)
├── BiomeDecorator       - places ores, trees, flowers, grass, and other features
│   └── TheEndBiomeDecorator - End-specific decoration (obsidian spikes, podium)
├── BiomeCache           - caches biome lookups in 256x256 blocks
└── Layer (pipeline)     - transforms noise into biome IDs through chained layers

Key source files

File	Purpose
Biome.h / Biome.cpp	Base class, static biome registry, mob spawns, default properties
BiomeSource.h / BiomeSource.cpp	Provides biomes for any (x, z) coordinate using the Layer pipeline
FixedBiomeSource.h	Single-biome source for superflat worlds
BiomeDecorator.h / BiomeDecorator.cpp	Feature placement: ores, trees, flowers, mushrooms, springs
TheEndBiomeDecorator.h	End decoration: obsidian spikes, podium, dragon spawning
Layer.h / Layer.cpp	Base layer class and getDefaultLayers() pipeline builder
BiomeInitLayer.h / BiomeInitLayer.cpp	Assigns initial biome IDs from a set of starter biomes
BiomeOverrideLayer.h	Debug layer that overrides biome data from a 216x216 byte array

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Biome base class

Biome stores all per-biome properties and keeps a static registry of 256 biome slots. Each biome gets created in Biome::staticCtor() using a builder-style chain.

Properties

Field	Type	Description
id	const int	Numeric biome ID (0-255), index into Biome::biomes[]
m_name	wstring	Display name
color	int	Map color (RGB hex)
topMaterial	byte	Surface block ID (default: grass)
material	byte	Sub-surface block ID (default: dirt)
temperature	float	Temperature value; controls snow/rain threshold
downfall	float	Rainfall amount; affects humidity classification
depth	float	Base terrain height (negative = below sea level)
scale	float	Terrain height variation
leafColor	int	Leaf tint color
m_grassColor	eMinecraftColour	Grass color enum (loaded from texture pack)
m_foliageColor	eMinecraftColour	Foliage color enum
m_waterColor	eMinecraftColour	Water color enum
m_skyColor	eMinecraftColour	Sky color enum
snowCovered	bool	Whether biome has snow on the ground
_hasRain	bool	Whether rain is enabled
decorator	BiomeDecorator *	Controls feature placement counts

Builder methods

The biome constructor chain uses these private/protected setters:

Method	Purpose
setTemperatureAndDownfall(float, float)	Set climate values
setDepthAndScale(float, float)	Set terrain shape
setName(wstring)	Set display name
setColor(int)	Set map color
setLeafColor(int)	Set leaf tint
setSnowCovered()	Mark as snow biome
setNoRain()	Disable rain
setLeafFoliageWaterSkyColor(...)	Set all four color enums at once (4J addition)

Climate logic

• Snow: A biome has snow if rain is enabled and temperature < 0.15f.
• Rain: A biome has rain if _hasRain == true and it doesn’t snow.
• Humidity: A biome counts as humid when downfall > 0.85f.

Colors for grass, foliage, water, and sky are loaded from the texture pack’s color table using per-biome eMinecraftColour enums instead of being computed from temperature/downfall like vanilla Java Edition does. This is a 4J Studios change.

Virtual methods

Method	Description
getTreeFeature(Random*)	Returns a Feature* for tree generation (biome picks the tree type)
getGrassFeature(Random*)	Returns a Feature* for tall grass/fern generation
getSkyColor(float temp)	Sky color at a given temperature
hasSnow()	Whether the biome gets snow
hasRain()	Whether the biome gets rain
isHumid()	Whether downfall > 0.85
getCreatureProbability()	Spawn probability for passive mobs
getDownfallInt()	Integer downfall (0-255 range)
getTemperatureInt()	Integer temperature (0-255 range)
getDownfall()	Raw float downfall value (4J addition)
getTemperature()	Raw float temperature value (4J addition)
decorate(Level*, Random*, int xo, int zo)	Run biome-specific decoration
getGrassColor()	Grass tint for this biome
getFolageColor()	Foliage tint (note the typo in the source)
getWaterColor()	Water tint (4J addition)

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Biome registry

All 23 biomes (BIOME_COUNT = 23) are created in Biome::staticCtor(). Here’s the full table straight from the source code:

ID	Name	Class	Temp	Downfall	Depth	Scale	Surface	Snow	Rain
0	Ocean	OceanBiome	0.5	0.5	-1.0	0.4	grass/dirt	no	yes
1	Plains	PlainsBiome	0.8	0.4	0.1	0.3	grass/dirt	no	yes
2	Desert	DesertBiome	2.0	0.0	0.1	0.2	sand/sand	no	no
3	Extreme Hills	ExtremeHillsBiome	0.2	0.3	0.3	1.5	grass/dirt	no	yes
4	Forest	ForestBiome	0.7	0.8	0.1	0.3	grass/dirt	no	yes
5	Taiga	TaigaBiome	0.05	0.8	0.1	0.4	grass/dirt	yes	no
6	Swampland	SwampBiome	0.8	0.9	-0.2	0.1	grass/dirt	no	yes
7	River	RiverBiome	0.5	0.5	-0.5	0.0	grass/dirt	no	yes
8	Hell	HellBiome	2.0	0.0	0.1	0.3	grass/dirt	no	no
9	Sky (The End)	TheEndBiome	0.5	0.5	0.1	0.3	dirt/dirt	no	no
10	Frozen Ocean	OceanBiome	0.0	0.5	-1.0	0.5	grass/dirt	yes	no
11	Frozen River	RiverBiome	0.0	0.5	-0.5	0.0	grass/dirt	yes	no
12	Ice Plains	IceBiome	0.0	0.5	0.1	0.3	grass/dirt	yes	no
13	Ice Mountains	IceBiome	0.0	0.5	0.3	1.3	grass/dirt	yes	no
14	Mushroom Island	MushroomIslandBiome	0.9	1.0	0.2	1.0	mycelium/dirt	no	yes
15	Mushroom Island Shore	MushroomIslandBiome	0.9	1.0	-1.0	0.1	mycelium/dirt	no	yes
16	Beach	BeachBiome	0.8	0.4	0.0	0.1	sand/sand	no	yes
17	Desert Hills	DesertBiome	2.0	0.0	0.3	0.8	sand/sand	no	no
18	Forest Hills	ForestBiome	0.7	0.8	0.3	0.7	grass/dirt	no	yes
19	Taiga Hills	TaigaBiome	0.05	0.8	0.3	0.8	grass/dirt	yes	no
20	Extreme Hills Edge	ExtremeHillsBiome	0.2	0.3	0.2	0.8	grass/dirt	no	yes
21	Jungle	JungleBiome	1.2	0.9	0.2	0.4	grass/dirt	no	yes
22	Jungle Hills	JungleBiome	1.2	0.9	1.8	0.5	grass/dirt	no	yes

Terrain shape explained

The depth and scale values directly affect how the noise generator shapes terrain:

• depth shifts the density curve up or down. Negative depth (like Ocean at -1.0) creates terrain below sea level. Positive depth raises it above.
• scale controls how rough and varied the terrain height is. High scale (like Extreme Hills at 1.5) means big height swings. Low scale (like Swampland at 0.1) means flat.

These values get smoothed with neighboring biomes during prepareHeights() using a 5x5 weighted kernel, so you don’t get hard edges between biomes.

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Biome subclasses

Each subclass tweaks mob spawns, decorator counts, tree types, and/or decoration behavior.

PlainsBiome (ID 1)

• Trees are disabled (treeCount = -999)
• Lots of grass (10), extra flowers (4)
• Default friendly mob spawns
• Uses the base getTreeFeature() which returns a normal oak tree (not that it matters since treeCount is negative)

DesertBiome (IDs 2, 17)

• Clears all friendly mob spawns (no passive mobs)
• Surface: sand over sand
• No trees, dead bushes (2), reeds (50), cacti (10)
• Custom decorate(): 1/1000 chance per chunk to place a DesertWellFeature

ExtremeHillsBiome (IDs 3, 20)

• Clears the friendlies list only (Sheep, Pig, Cow removed; chickens still spawn through friendlies_chicken)
• Custom decorate(): generates emerald ore (3-8 veins per chunk, Y range 4 to genDepth / 4)
• GENERATE_EMERALD_ORE is a compile-time constant set to true

ForestBiome (IDs 4, 18)

• Wolves added to friendlies_wolf (weight 5)
• Trees: 10 per chunk; 1/5 chance birch, 1/10 chance fancy oak, otherwise normal oak
• Grass count: 2
• getTreeFeature() returns BirchFeature, BasicTree, or TreeFeature based on random rolls

TaigaBiome (IDs 5, 19)

• Wolves added (weight 8)
• Trees: 10 per chunk; 1/3 chance pine, otherwise spruce
• Temperature set to 0.05 (snow-covered)
• Grass count: 1
• getTreeFeature() returns either PineFeature or SpruceFeature

SwampBiome (ID 6)

• Trees: 2 per chunk, always SwampTreeFeature
• Flowers are disabled (flowerCount = -999)
• Dead bushes (1), mushrooms (8), reeds (10), clay (1), waterlilies (4)
• getTreeFeature() always returns SwampTreeFeature

RiverBiome (IDs 7, 11)

• Clears friendlies, friendlies_chicken, and friendlies_wolf (no passive land mobs on rivers)
• Inline constructor in header; no extra decoration
• Frozen River (ID 11) uses the same class but with temperature 0.0 and setSnowCovered()

HellBiome (ID 8)

• Clears all default mobs
• Enemies: Ghast (weight 50), Zombie Pigman (weight 100), Magma Cube (weight 1)
• No rain
• Note: Nether fortress mobs (Blaze, etc.) are handled separately by NetherBridgeFeature::getBridgeEnemies()

TheEndBiome (ID 9)

• Clears all default mobs; adds Enderman (weight 10) as enemy
• Surface: dirt/dirt
• Uses TheEndBiomeDecorator instead of the default decorator
• TheEndBiomeDecorator holds:
  • spikeFeature: a SpikeFeature for obsidian pillars
  • endPodiumFeature: an EndPodiumFeature for the exit portal
  • Static SpikeValA[8] array containing pre-computed spike data (chunk coordinates, world position, radius)

OceanBiome (IDs 0, 10)

• Clears friendlies, friendlies_chicken, and friendlies_wolf (no passive land mobs)
• Inline constructor in header
• Frozen Ocean (ID 10) uses the same class but with temperature 0.0 and setSnowCovered()

IceBiome (IDs 12, 13)

• No extra customization beyond the base class; snow coverage is set through setSnowCovered() in staticCtor()
• Ice Mountains (ID 13) has higher depth (0.3) and scale (1.3) for mountainous terrain

MushroomIslandBiome (IDs 14, 15)

• Clears all mob lists (enemies, friendlies, water creatures)
• Adds Mooshroom to friendlies_mushroomcow (weight 8, groups of 4-8)
• Surface: mycelium
• Trees/flowers/grass all set to -100 (basically disabled); mushrooms (1), huge mushrooms (1)
• The shore variant (ID 15) has depth -1.0 and scale 0.1 for the water-level transition

BeachBiome (ID 16)

• Clears friendlies and friendlies_chicken (Sheep, Pig, Cow, Chicken removed; friendlies_wolf isn’t cleared but wolves are never added to beaches anyway)
• Surface: sand/sand
• Trees disabled (treeCount = -999), dead bushes (0), reeds (0), cacti (0)

JungleBiome (IDs 21, 22)

• High tree count (50), grass (25), flowers (4)
• Adds Ocelot to enemies (weight 2, groups of 1) and extra Chickens to friendlies (weight 10, groups of 4). Note: added to the main friendlies list, not friendlies_chicken
• Tree selection in getTreeFeature():
  • 1/10 chance: fancy oak (BasicTree)
  • 1/2 chance: ground bush (GroundBushFeature with jungle trunk/leaf types)
  • 1/3 chance: mega jungle tree (MegaTreeFeature)
  • Otherwise: normal jungle tree (TreeFeature with jungle trunk/leaf types and vine features)
• Custom getGrassFeature(): 1/4 chance fern, otherwise tall grass
• Custom decorate(): places 50 VinesFeature per chunk after the base decoration

RainforestBiome

• Not assigned to any biome ID in staticCtor(); seems to be an unused/legacy biome class
• Tree selection: 1/3 fancy oak, otherwise normal oak

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Mob spawning

The base Biome constructor sets up default spawn lists:

Category	Mobs	Weights
friendlies	Sheep (12), Pig (10), Cow (8)	groups of 4
friendlies_chicken	Chicken (10)	groups of 4
enemies	Spider (10), Zombie (10), Skeleton (10), Creeper (10), Slime (10), Enderman (1)	groups of 4 (Enderman: 1-4)
waterFriendlies	Squid (10)	groups of 4

MobSpawnerData

Each entry is a MobSpawnerData that extends WeighedRandomItem:

class MobSpawnerData : public WeighedRandomItem {
    eINSTANCEOF mobClass;  // Mob type enum
    int minCount;           // Minimum group size
    int maxCount;           // Maximum group size
};

4J mob category split

4J Studios split chickens, wolves, and mooshrooms into their own MobCategory lists (friendlies_chicken, friendlies_wolf, friendlies_mushroomcow) for tighter spawn control. The getMobs() method looks at the MobCategory to return the right list.

This split lets the game control spawn rates for these animals independently. For example, chickens can have different spawn caps than other passive mobs.

Per-biome mob changes summary

Biome	Friendlies	Friendlies (chicken)	Friendlies (wolf)	Enemies	Water
Plains	Default	Default	—	Default	Default
Desert	Cleared	Cleared	—	Default	Default
Extreme Hills	Cleared	Default	—	Default	Default
Forest	Default	Default	Wolf (5)	Default	Default
Taiga	Default	Default	Wolf (8)	Default	Default
Swamp	Default	Default	—	Default	Default
River	Cleared	Cleared	Cleared	Default	Default
Hell	Cleared	Cleared	—	Ghast/ZPigman/MagmaCube	Cleared
The End	Cleared	Cleared	—	Enderman (10)	Cleared
Ocean	Cleared	Cleared	Cleared	Default	Default
Ice Plains/Mountains	Default	Default	—	Default	Default
Mushroom Island	Cleared	Cleared	—	Cleared	Cleared + Mooshroom
Beach	Cleared	Cleared	—	Default	Default
Jungle	Default + Chicken(10)	Default	—	Default + Ocelot(2)	Default

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BiomeDecorator

BiomeDecorator handles per-chunk feature placement. Each biome can override decorator counts in its constructor.

Default decorator counts

Feature	Count	Description
treeCount	0	Trees per chunk (10% bonus chance for +1)
flowerCount	2	Yellow flower placements (1/4 chance rose)
grassCount	1	Tall grass placements
deadBushCount	0	Dead bush placements
mushroomCount	0	Mushroom placement attempts
reedsCount	0	Sugar cane placements
cactusCount	0	Cactus placements
waterlilyCount	0	Waterlily placements
hugeMushrooms	0	Huge mushroom placements
sandCount	3	Sand patches
clayCount	1	Clay patches
gravelCount	1	Gravel patches
liquids	true	Whether to place water/lava springs

Feature instances

BiomeDecorator creates these feature objects in _init():

Field	Feature Class	Purpose
clayFeature	ClayFeature	Clay disk patches
sandFeature	SandFeature	Sand disk patches
gravelFeature	SandFeature	Gravel disk patches (same class as sand)
dirtOreFeature	OreFeature	Dirt vein generation
gravelOreFeature	OreFeature	Gravel vein generation
coalOreFeature	OreFeature	Coal ore veins
ironOreFeature	OreFeature	Iron ore veins
goldOreFeature	OreFeature	Gold ore veins
redStoneOreFeature	OreFeature	Redstone ore veins
diamondOreFeature	OreFeature	Diamond ore veins
lapisOreFeature	OreFeature	Lapis lazuli ore veins
yellowFlowerFeature	FlowerFeature	Dandelion placement
roseFlowerFeature	FlowerFeature	Rose/poppy placement
brownMushroomFeature	FlowerFeature	Brown mushroom placement
redMushroomFeature	FlowerFeature	Red mushroom placement
hugeMushroomFeature	HugeMushroomFeature	Giant mushroom placement
reedsFeature	ReedsFeature	Sugar cane placement
cactusFeature	CactusFeature	Cactus placement
waterlilyFeature	FlowerFeature	Lily pad placement

Friend classes

These biome classes are declared as friend of BiomeDecorator so they can directly modify the protected count fields:

DesertBiome, ForestBiome, PlainsBiome, SwampBiome, TaigaBiome, MushroomIslandBiome, BeachBiome, JungleBiome

Ore generation

decorateOres() places ores with these settings:

Ore	Veins/chunk	Vein size	Max height
Dirt	20	32	genDepth
Gravel	10	32	genDepth
Coal	20	16	genDepth
Iron	20	8	genDepth/2
Gold	2	8	genDepth/4
Redstone	8	7	genDepth/8
Diamond	1	7	genDepth/8
Lapis Lazuli	1	6	Average around genDepth/8

Lapis uses decorateDepthAverage() for a triangular distribution centered at genDepth/8.

Decoration order

1. Ores
2. Sand, clay, gravel patches
3. Trees (count + 10% bonus)
4. Huge mushrooms
5. Flowers (yellow + rose)
6. Tall grass
7. Dead bushes
8. Waterlilies
9. Mushrooms (brown + red)
10. Additional brown/red mushroom attempts (global, outside biome count)
11. Sugar cane (biome count + 10 extra)
12. Pumpkins (1/32 chance)
13. Cacti
14. Water springs (50 per chunk)
15. Lava springs (20 per chunk)

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Layer pipeline

Biome selection is driven by a chain of Layer objects, built in Layer::getDefaultLayers(). Each layer transforms an integer grid (intArray) representing biome IDs or terrain categories.

Layer base class

Layer uses a linear congruential generator (LCG) with the constant 6364136223846793005 for deterministic pseudo-random output. The initRandom(x, y) method seeds per-cell randomness, and nextRandom(max) returns values in [0, max).

The PS Vita build includes a special fast-divide optimization (libdivide) for the modulo operation in nextRandom().

Key methods:

static LayerArray getDefaultLayers(__int64 seed, LevelType *levelType);
Layer(__int64 seedMixup);
virtual void init(__int64 seed);
virtual void initRandom(__int64 x, __int64 y);
virtual intArray getArea(int xo, int yo, int w, int h) = 0;
int nextRandom(int max);

Pipeline construction

The full layer chain for normal world generation:

IslandLayer(1)
  -> FuzzyZoomLayer(2000)
  -> AddIslandLayer(1)
  -> ZoomLayer(2001)
  -> AddIslandLayer(2)
  -> AddSnowLayer(2)
  -> ZoomLayer(2002)
  -> AddIslandLayer(3)
  -> ZoomLayer(2003)
  -> AddIslandLayer(4)
  -> [branch: river pipeline]
  -> [branch: biome pipeline]

River branch:

  -> ZoomLayer (1x)
  -> RiverInitLayer(100)
  -> ZoomLayer (zoomLevel + 2 times)
  -> RiverLayer(1)
  -> SmoothLayer(1000)

Biome branch:

  -> ZoomLayer (1x)
  -> BiomeInitLayer(200)
  -> ZoomLayer (2x)
  -> RegionHillsLayer(1000)
  -> [zoomLevel iterations of ZoomLayer, with:]
      i=0: AddIslandLayer(3), AddMushroomIslandLayer(5)
      i=1: GrowMushroomIslandLayer(5), ShoreLayer(1000), SwampRiversLayer(1000)
  -> SmoothLayer(1000)
  -> RiverMixerLayer(100)  [merges river + biome]
  -> [optional BiomeOverrideLayer for debug]
  -> VoronoiZoom(10)       [final zoom for block-level precision]

The zoomLevel is normally 4, or 6 for LevelType::lvl_largeBiomes.

Layer types

Layer	Purpose
IslandLayer	Initial noise: random land (1) vs ocean (0)
FuzzyZoomLayer	2x zoom with random interpolation
ZoomLayer	Standard 2x zoom with bilinear-like interpolation
AddIslandLayer	Randomly converts ocean cells to land
AddSnowLayer	Marks cold regions (value 3+4) for snow biomes
AddMushroomIslandLayer	Places mushroom island biome in isolated ocean
GrowMushroomIslandLayer	Expands mushroom islands by region-growing (4J custom)
BiomeInitLayer	Assigns actual biome IDs from the starter biome set
RegionHillsLayer	Converts base biomes to their hills variants
ShoreLayer	Adds beach/shore transitions
SwampRiversLayer	Integrates swamp-adjacent rivers
RiverInitLayer	Seeds the river noise pattern
RiverLayer	Generates river biome from noise
RiverMixerLayer	Combines river and biome layers
SmoothLayer	Smooths biome boundaries
VoronoiZoom	Final cell-based zoom for block-level biome resolution
BiomeOverrideLayer	Debug: overrides biomes from a 216x216 byte array

BiomeInitLayer starter biomes

The set of biomes available for initial assignment depends on LevelType:

• lvl_normal_1_1 (pre-1.2.3): Desert, Forest, Extreme Hills, Swampland, Plains, Taiga (6 biomes)
• Other level types: Same plus Jungle (7 biomes)

Cold regions (snow layer value >= 2) are limited to Taiga or Ice Plains.

RegionHillsLayer mappings

RegionHillsLayer converts base biomes to their hills variants:

Base Biome	Hills Variant
Desert (2)	Desert Hills (17)
Forest (4)	Forest Hills (18)
Taiga (5)	Taiga Hills (19)
Extreme Hills (3)	Smaller Extreme Hills (20)
Jungle (21)	Jungle Hills (22)

Other biomes (Plains, Swampland, etc.) don’t have hills variants and stay the same.

4J Studios modifications to the layer pipeline

• Mushroom islands: Moved 3 zoom levels later than vanilla Java, making them roughly 1/8 the original size. A custom GrowMushroomIslandLayer then region-grows them back into compact shapes that fit within the console world boundaries.
• Shore layer: Applied at zoom iteration 1 instead of 0.
• Large biomes: zoomLevel bumped from 4 to 6 for lvl_largeBiomes.

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BiomeSource

BiomeSource is the main way to query biomes at world coordinates. It holds two Layer references:

• layer: the main biome layer (used for getBiomeBlock())
• zoomedLayer: the Voronoi-zoomed layer (used for block-level precision)

Key methods

Method	Description
getBiome(ChunkPos*)	Returns the biome for a chunk position
getBiome(int x, int z)	Returns the biome at block coordinates
getBiomeBlock(int x, int z, int w, int h)	Returns a rectangular array of biomes
getBiomeIndexBlock(...)	Returns biome indices as byte array
getRawBiomeBlock(...)	Gets biome data without Voronoi zoom
getRawBiomeIndices(...)	Gets raw biome indices (4J addition)
getTemperature(int x, int y, int z)	Temperature at a position (scaled by altitude via scaleTemp())
getDownfall(int x, int z)	Downfall value at a position
getTemperatureBlock(...)	Bulk temperature query
getDownfallBlock(...)	Bulk downfall query
containsOnly(int x, int z, int r, vector<Biome*> allowed)	Checks if an area only has the specified biomes (used by structure placement)
containsOnly(int x, int z, int r, Biome* allowed)	Single-biome version
findBiome(int x, int z, int r, Biome* toFind, Random*)	Searches for a specific biome within a radius
findBiome(int x, int z, int r, vector<Biome*> allowed, Random*)	Searches for any of several biomes
findSeed(LevelType*)	Static method that searches for a valid seed (PS Vita has early-out support)
getPlayerSpawnBiomes()	Returns the list of biomes valid for player spawning

Temperature scaling

BiomeSource::scaleTemp() adjusts temperature based on altitude. This is a 4J addition brought forward from version 1.2.3. Higher positions are colder.

FixedBiomeSource

Used for superflat worlds. Always returns the same biome with constant temperature and downfall values. Every spatial query returns that fixed biome.

BiomeCache

BiomeCache caches biome data in 256x256 block regions (CACHE_DIAMETER = 256) so the system doesn’t have to re-run the layer pipeline for the same area. BiomeSource creates and manages this cache internally. Cache blocks are accessed via getBlockAt().

MinecraftConsoles Differences

The biome system is basically the same between LCEMP and MC. Both have 23 biomes (BIOME_COUNT = 23) with the same IDs, names, and properties. The biome registry, layer pipeline, and decorator system are identical in structure.

The one notable difference is that MC’s SwampBiome now participates in the scattered feature system for witch hut generation. The swamp biome’s enemy list can include Witch spawns near witch hut structures. In LCEMP, swamps don’t have any special structure-related spawning.

Otherwise, the biome classes, decorator counts, and mob spawn lists are the same across both codebases.