Creep Blisters are evolutionary defenses that can be mutated by Zerg Creep. These pockets contain a combination of compressed toxic gas and unstable substances used by explosive strains. Similar to a biological landmine, Creep blisters grow under the surface and detonate at the slightest trigger. The force of the explosions is enough to throw a Siege Tank several feet into the air. Anything that survives is usually covered in corrosive acids that eats away at armor while nearby combat strains move in for the kill. Special abilities: