Pharaoh Katchu Pitchu was the ruler of the area around Megakat City long before even Megalith City existed. Little is known about him except that he was a giant, Demon-like monster who commanded an army of giant mummies which he controlled with a special headdress. Somehow or another, the Pharaoh and his mummies came under the command of the Pastmaster, and Katchu Pitchu's life-force became connected to the headdress.
The Pastmaster returned to the pyramid many centuries later, using the headdress to revive all of the mummies except for Katchu Pitchu himself. He did eventually summon forth Katchu Pitchu, but only as a last-ditch effort to destroy the Swat Kats after the vigilantes had defeated all of the regular mummies. Unlike his mummies, the Pharaoh (who by this point seemingly had lost all self-awareness) was not affected by bright light of any kind, but because his life-force was connected to the headdress, he died and melted away into nothing when Razor destroyed it.