Blight Slime

The Blight Slime is a decently uncommon Pre-Hardmode slime that spawns in the Corruption/Crimson biome. It has two variants, which appear depending on the world's evil biome. It drops Blighted Gel, a crafting material used in the crafting of the Overloaded Sludge, which is the summoning item for The Slime God, as well as various other recipes such as the Zen Potion.

Trivia

 * Blight Slimes seem to be smaller versions of The Slime Gods with the colors swapped.
 * Only the Crimulan Blight Slime can drop Carnage despite the blight slimes being opposites of each other.