What is Alex's Caves?
Alex's Caves by AlexModGuy (of Alex's Mobs) adds rare, self-contained cave biomes hidden deep underground, each functioning like a miniature dimension with exclusive mobs, blocks, mechanics, and boss-tier encounters. It released for Forge on 1.20.1 (with a NeoForge port available) and became one of the most celebrated content mods of its generation.
The biomes are deliberately rare: finding one is an expedition goal, guided by maps looted from surface structures.
The Cave Biomes
- Magnetic Caves – magnetite everywhere, gravity-bending magnetic fields, and metal-themed mobs; source of magnet-based gear and machines.
- Primordial Caves – a lost world of jungle and amber populated by dinosaurs (Grottoceratops, Tremorsaurus, Vallumraptor and kin), with tameable species and fossil-tech items.
- Toxic Caves – radioactive slime, acid, and uranium; requires (and provides) a Hazmat Suit and feeds nuclear-flavored gadgets, including famously dramatic explosives. Radiation is a real status effect to manage.
- Abyssal Chasm – a drowned trench with deep-sea creatures and a craftable submarine for exploring it.
- Forlorn Hollows – dusty catacombs with undead horrors and archaeology-flavored loot.
- Candy Cavity – the dessert-themed addition, all gingerbread, frosting, and sugar mobs.
Each biome's resources build gear usable outside it, so every discovery permanently expands your toolkit.
Finding the Caves
Cave biomes announce themselves through maps: surface and underground structures contain Cave Maps pointing to the nearest instance of a specific biome. Watch for unusual terrain tells too — magnetic distortion effects, scattered biome-specific blocks near entrances.
Come prepared per biome: hazmat gear for Toxic Caves, water breathing for the Abyssal Chasm, and serious combat readiness for Forlorn Hollows. The in-game Cave Book (guide item) documents each biome's hazards as you discover them.
Alex's Caves FAQ
What version is Alex's Caves on?
Minecraft 1.20.1 on Forge, with NeoForge compatibility builds. Newer game versions were not covered at the time of writing.
How do I find the cave biomes in Alex's Caves?
Loot Cave Maps from structures; each map marks the nearest instance of a specific cave biome. The biomes are rare by design, so maps beat blind caving.
Does Alex's Caves require Alex's Mobs?
No, it is standalone (requiring the Citadel library). The two mods share an author and pair well but install independently.