Krackus is the former chief scientist and inventor of The Cluster. He is protrayed as "mad" and often creates inventions that usually end humiliatingly for Vexus's team. However, one of his inventions did work, his disassembler, as seen in the episode Around the World in Eighty Pieces. As a running gag, every mechanical object around him, be it his own or not, malfunctions and crumble to pieces, and he often pronounces Jenny's name wrong.

Krackus is voiced by Jim Ward.