The graffiti seen on the background walls mentions the names of TMNT villains: the word "Shred" - the Shredder, the Turtles' archnemesis and leader of the Foot Clana man's head with insect eyes - Baxter Stockman, a scientist who mutated into a half-fly hybrida rat with the word "King" - the Rat King, a mutant who can control rats.