Beneath Fauna

Axolotls can be found in the top and middle layers, usually swimming around in pools of water.

Frogs can be found in the top and middle layers. They can be tamed and eaten.

Mammutilations are undead Mammoths. You can put them out of their misery for some Wool.

Red Elk are found near the bottom, usually swimming around in lava. They can be slain for Lavaproof Hides.

Zombie Horses can't be tamed or ridden, but they can pull an Animal Crank.

Ice Jellies are found in the Salt Caves biome. They cool down nearby players.

Plant Jellies are found in the Muggy Bog and Thorny Grove biomes. Their slime balls can be used as Green compost.

Glowberry Jellies are found in the Lush Hollow biome. Their slime balls can be boiled into Sugar.

Spring Jellies are found in the Geothermal Springs biome. Their slime balls are a renewable source of Spring Water.

Biotite Jellies are found in the bottom layer. Their slime balls are a renewable source of Potassium, Magnesium, and Fluorine.

Lava Jellies are found in the bottom layer. They heat up nearby players, which may be useful if you live somewhere cold.

Latex Jellies can only be bred from a Plant Jellie and Lava Jellie. Their slime balls are a source of Latex.

You can find Piglins in almost every biome throughout the Beneath. They can be traded with like in vanilla.

Crocodiles can be found in the top and middle layers, waiting in ambush!

Phantoms naturally spawn in the middle and bottom layers, regardless of how much sleep you're getting. They can be turned into Clothing.

Kaolin Klayzes can be found in the Lush Hollow biome, guarding the Kaolin!

Graphite Glayzes can be found in the bottom layers. Careful they don't knock you into lava!

Cliff Hangers can be found on various ceilings, hooking players who walk below them. Hit them with a ranged attack to make them let go!

Leaf Hangers can be found in pools of Salt Water, hooking players who walk into their trap. Hit them to make them let go of you!

Various species of Endermen appear all over. The mushroom one is completely passive, while the others are all neutral.

Spectres are ghosts of adventurers past, and come in three varieties. They are a source of Feathers.

The Wicked is a ghost that can posess nearby mobs to give them buffs! If no mob is nearby, they use a ranged attack. They drop wax.

Ghouls are blind monsters that use echolocation to find prey. They are neutral unless you're within their 'scan' radius!

The Bewereager is an aggressive monster that can also jump up to you! It buffs itself and attacks in short bursts.