Unbeknownst to the archeological team at the Katchu Pichu dig site led by Dr. Abby Sinian, these multi-story monster laid dormant underground within the Lost Pyramid of Katchu Picchu until the Pastmaster, using the Jeweled Headdress of Katchu Picchu, 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.