The Aether variant, Acid biome! It's a biome with the acid liquid which disintegrates all mineable blocks under it; and in journey mode or higher, disintegrates harder blocks like ebonstone or obsidian. (I know this is meaningless) If you throw an item into acid, it comes out as... ...Absolutely nothing! It's gone! Also, there are acid slimes in this biome, too! Like in D&D, they absorb everything in their path, but this time, including the ground! Another thing, you can have a super acid soaker, which will turn into its endless acid ammo (I'm bored of using that word, but have nothing else to put in place) which will leak forever (Remember Minecraft?)...