Hybrid biomes are those created by the requirements being met for multiple biomes in a certain area.

5.6 Corrupted, Crimson, and Hallowed IceĪlthough many basic biomes appear at the world generation or are triggered by events, hybrid biomes may be synthesized by world mechanics or through player action.5.5 Corrupted, Crimson, and Hallowed Desert.In pre-Hardmode, the evil biomes will only overtake other biomes via grass, ice, sand, and stone, but once Hardmode begins all three biomes can spread directly through most soil blocks, vines, and thorny bushes. The Corruption, Crimson, and Hallow are all 'contagious' biomes which spread to certain adjacent blocks. The world's evil biome roots deeper with the Underground Corruption/ Crimson, and the Hallow and Underground Hallow form as well. Once Hardmode is activated, a few new biomes form. The Glowing Mushroom biome also appears in the Cavern layer, and the Underworld spans the entire bottom of the world. These include the Underground Desert, Ice biome, and Underground Jungle. Going any deeper, the player will find unique subterranean variants of most of these. These Surface biomes extend into the Underground layer. Biomes on the Surface layer include Forests, Deserts, the Snow biome, the Jungle, the Dungeon, the evil biome (either the Corruption or the Crimson), and at the far ends of the world, the two Oceans. Spanning the world's ceiling is the Space biome. Every biome has its own characteristic terrain blocks, collectible items, backdrops, enemies, critters, theme music, background walls, Angler quest fish, and other features. Biomes are the different types of areas that any Terraria world can contain.

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