Noxious Enterprise's Super SPU-31 Liquid-Cooled Mobile Processing Unit, also known as SPU-31, is a robot that Plankton created to try to steal the Krabby Patty Secret Formula and replace Karen.
It has a large bubbly blue center with a substance in it, and has robot legs to hold itself up.
SPU-31 fought alongside the Command Module
and the T-119A Compumatic
, until Plankton joined the three robots to make one giant robot. SPU-31 made up the bottom of the robot. This robot was only seen in the episode, "Komputer Overload