Baxter Stockman is a villain in the Teenage Mutant the Ninja Turtles franchise.
Baxter first appeared in the inital five part miniseries that lead to the show. Like in the Mirage and 2003 versions, he created the mousers to rid the city of vermin, but in this version, the company he proposed them to turned him down, believing they would be bad for business.
However, the Shredder, seeing potential for the mousers, took Baxter on his proposal, and used them in a failed attempt to destroy the Ninja Turtles. After this, Baxter was committed to an insane asylum after trying to tell the police about the Turtles' existence.
Awhile later, Shredder broke him out of the asylum, and hr was forced to work for him, suffering much abuse from the evil ninja master. Finally having enough of Baxter's stupidity, Shredder and Krang decided to kill him by throwing him into a disintegrator unit. But a small fly entered the same unit, and rather than killing him, the energy merged him with the fly, turning him into a half man-half fly creature. Blaming both the Shredder and the Turtles for this, Baxter swore revenge on all of them.