Baxter Stockman

Misguided inventor who invented the MOUSERS
Worked for Shredder, failed at capturing the TMNT multiple times
Tossed into a mutagen-powered disintegration chamber by Krang;
Mutated into a humanoid housefly, convinced that it was the Turtles’ fault
Tried to trap the Turtles but got himself caught in it instead,
Shifted out of phase with our dimension, became invisible & intangible
Got struck by lightning which realigned his molecules with the rest of reality
Attacked the Turtles one more time & got himself stranded in an dimensional limbo