The Corruption is a biome in Terraria: Otherworld that is likely similar to the The Corruption found in the original game. It is implied from the description on the official website that the biome has spread over much of the terrain, and the various Purifying Towers the player may find or create will prevent it from spreading to certain areas.
A preview of the music for the Corruption was shared in the OST Preview Trailer.
A player in a early version of the game, shooting a group of enemies.
A player standing in the corruption.