Core Keeper Biomes
The ring layout of the underground: which biome sits where, what it offers and what to watch out for. Core Keeper biomes are arranged in concentric rings around the Core, with angular positions set by the world seed.
Ring layout of the underground
The Undergrounds
Center · 0–140 tiles
Danger: Low · Resources: Copper Ore, Tin Ore, Wood, Stone, Food crops
Note: Default biome; safe starting area around The Core
The Clay Caves
Inner ring · 150–450 tiles
Danger: Medium · Resources: Clay, Iron Ore, Larva Hive entrance
Note: Angular position varies by seed
The Forgotten Ruins
Inner ring · 150–450 tiles
Danger: Medium · Resources: Stone, Scarlet Ore, Ruins chests
Note: Also called the stone biome; position varies by seed
The Great Wall
Gate ring · 450–520 tiles
Danger: High · Resources: None (barrier)
Note: Gates access to outer biomes until progression is met
Azeos' Wilderness
Outer ring · 520–1200 tiles
Danger: High · Resources: Gold Ore, Mold sub-biome, Azeos arena
Note: One of three outer biomes; counter-clockwise order by seed
The Sunken Sea
Outer ring · 520–1200 tiles
Danger: High · Resources: Fish, Coral, Omoroth arena
Note: Water-filled outer biome
The Desert of Beginnings
Outer ring · 520–1200 tiles
Danger: High · Resources: Sand, Cactus, Ra-Akar arena
Note: Hottest outer biome
The Passage
Beyond outer ring · ≈1200+ tiles
Danger: Very High · Resources: Endgame materials, Titan arenas
Note: Endgame area; reachable after main progression
