The six Alex's Caves biomes, explained

Every Alex's Caves biome is built around a single idea, with its own blocks, creatures, lighting, fog and music. This overview covers the basics of each. For full recipes and numbers, the in-game Cave Compendium and the community wiki go deeper.

Magnetic Caves

A cavern of metal and magnetism. The theme runs through the equipment you can make here: tools and devices that attract or repel, conveyor and pulley-style machinery, and a gauntlet built around magnetic force. The local creatures are mechanical in flavour.

Bring: a solid melee weapon and patience with the unusual physics. Its tablets can turn up in Nether bastions as well as cabins.

Primordial Caves

A prehistoric jungle underground, with lush plants, caveman houses and a range of dinosaurs. Some are peaceful and can be tamed; others are dangerous. The Luxtructosaurus, a boss added in the 1.1 update, lives here.

Bring: armour, food and a plan for large hostile creatures. Primordial tablets can appear in suspicious sand at desert temples and wells.

Toxic Caves

A radioactive, acid-filled biome with glowing green hazards. Radiation is a real mechanic here, so protective gear matters. The mod's hazmat armour set exists for exactly this place. The Tremorzilla boss is associated with this biome.

Bring: protection against radiation and acid, and a quick exit. Jungle temples can hold its tablets.

Abyssal Chasm

A deep-ocean trench, dark and pressurised, reached from below the sea. It is home to the Deep Ones, an underwater civilisation that can turn hostile if you keep attacking them or become friendly if you trade with them using pearls. The mod's diving gear is designed for this biome.

Bring: water-breathing options, light and something to trade. Ocean ruins and buried treasure can hold its tablets.

Forlorn Hollows

The darkest and most openly hostile biome, nearly pitch black. Underzealots perform rituals here, and a ritual gone wrong can create the Forsaken, a huge bat-like boss with sonic attacks.

Bring: plenty of light, strong armour and a careful approach. Woodland mansions can hold its tablets.

Candy Cavity

The newest biome, added in the 2.0 update line: a cave of sweets and sugary terrain with its own creatures and a gingerbread armour set. It is the most playful of the six, though not entirely harmless.

Bring: the usual exploration kit, and curiosity.

Quick comparison

Ready to go looking? The biome-finding guide explains cabins, tablets and maps.