Unbeknownst to the archeological team at the Katchu Pichu dig site led by Dr. Abby Sinian, these multi-story monster laid dormant underground until the Pastmaster, using the Jeweled Headdress of Katchu Pichu, rose the pyramid and awoke the Giant Mummies to do his bidding. They proved to be durable adversaries for both the Enforcers and the SWAT Kats, appearing to be indestructible foes, until the SWAT Kats discovered they could be defeated by attacking their visors. With their eyes exposed to light, they dissolved into a pink masses of flesh.
Each mummy carried a sidearm that shot red bolts of energy, capable of destroying aircraft and vehicles. The mummies also demonstrated considerable strength, able to lift and throw large vehicles with ease.
Most of the mummies were destroyed by the SWAT Kats and the Enforcers after learning of their weakness. After the destruction of the Jewled Headdress of Katchu Pichu, it is assumed that any remaning mummies, as demonstrated by the summoned Katchu Pichu himself, dissolved away.