The Mind-Worms are genetically modified mutant worms created by Baxter Stockman. They bore into their host's brain and make their victims fall under the Mind Control Serum. They were used on Dr. Tyler Rockwell, Karai, Slash, and Raphael. The worms can't handle emotions and as result they leave their host's body. The worms are also vulnerable to Rockwell's psychic powers, and seem to dislike Healing Hands as Splinter uses this ancient technique to make Karai spit out the mind-worm.