Noxious Enterprise's Super SPU-31 Liquid-Cooled Mobile Proccesing Unit is a robot that Plankton created to try to steal the Secret Formula and replace Karen. SPU-31 fought with the other two robots that Plankton created. Until Plankton joined the three robots to make one giant robot. SPU-31 made up the bottom of the robot.
It looks like a blue glob of hair gel with four legs.