Worm Tooth

Worm Tooth is a crafting material dropped by Devourers in The Corruption. It appears to be the tooth of the Devourers. Unlike most Corruption items, it does not have a Crimson equivalent, rendering its recipes uncraftable in a Crimson world prior to Hardmode without bringing over items from a Corrupt world. However, in Hardmode, when the Dryad is in the Graveyard biome, she sells the seeds of the world evil opposite of the current world evil (i.e. Corrupt Seeds in a Crimson world and Crimson Seeds in a Corrupt world). This means the player can create an artificial Corrupt biome in a Crimson world, and therefore allow Devourers to spawn and drop Worm Teeth.