Zed is the name assumed by the robot created by scientist Lieter Greenbox that was originally designed to repair anything that was damaged.
The Metallikats stole the invention to repair their injuries and contaminated its' programming with their criminal personalities. Zed then created armor and weapons for itself after assimilating the metallic components needed. Zed disliked the Metallikats' lowly ambitions and south to to cause world domination as its' purpose. Zed was too difficult to control since Mac Mange failed to do that which horrified his wife Molly. The Enforcers were useless in stopping Zed since it assimilated their weaponry. The Swat Kats, Dr. Greenbox, and Molly (who was desperate to get Mac back) took on Zed again at PumaDyne where the Enforcers were being incompetent. Zed was able to assimilate Molly and fuse with Dr. Greenbox, who didn't want to destroy his most valid accomplishment. The Swat Kats destroyed the micro-brain just before it would have nuked Megakat City and the rest of the world.
- Zed was voiced by Charlie Adler in the original English version and by Tomomichi Nishimura in the Japanese dub, and this character appeared only in the episode "Unlikely Alloys".