Defiled Lands - Lykrast/DefiledLands GitHub Wiki

Defiled Lands are a type of biome that will occasionally spawn in the Overworld, they come in 7 variations (Desert, Plains, Hills, Swamplands, Ice Plains, Tenebra Forest, Vilespine Forest).

The ground of such biomes are defiled and will spread that defilement to nearby blocks as long as it's within the biome itself. They will also harbor a variety of unique plants and monsters, as well as custom ores once it spreads underground.

Underground, Defiled Dungeons will spawn. They look like vanilla dungeons, only made of Defiled Stone Bricks, having special defiled themed loot and spawning monsters from the defiled lands.