Brimstone Beaches

Flesh garden

The walls are made of bone. Bones stick out of the ground. There's bone inside the caves and floor and ceiling. Bones. Warped and crimson vines, and giant red and brown mushrooms and nether fungi, grow here too.

Molten brackets

Huge shelves of obsidian and basalt with magma at their edges. Smaller ones stick out of the walls. Dark spores float in the air. My favourite biome.

Soul sand beach

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Glacier (with a distinct lack of skeletons for some reason)

Packed ice on the floor is mixed with blue ice, and solid snow with powder snow. There's a bit of soul sand too.