The perentie is a known species of monitor lizard, which is the biggest in Australia and the third biggest in the world. They inhabit western and central Australia. Perenties typically reach 5.5 to 7-feet long, but the largest confirmed perentie specimen was 8.2 feet long. Occasional reports of perenties, or a species of perentie much larger, have been reported, reaching 18 ft. These giant perenties, or as the Aboriginals call it— the Debil Debil, coming from “devil”, with the word repeated to emphasize its large size. They’re reported as being so large it can make an ox fall over by a sweeping blow by their tail. Giant Perenties are described as moving in an awkward galloping motion. Most sightings are by Aboriginals due to the very remote location of them, with only a handful of outsiders seeing them. Although this cryptid is very similar to the Burrunjor, and possibly even the same species, giant perenties are differentiated by their less bulky bodies, longer necks, yellow and black skin and slightly shorter size.
One of the earliest, and most frightening encounters with a giant perentie was in the spring of 1899. That year, English Australian explorer Ernest Favenc, known for surveying much of the Gulf of Carpentaria, claimed to have encountered a giant perentie-like lizard his Aboriginal guides called "gonderanup", in the outback of Central Australia. He claimed that one night when his party was resting, they heard one of their horses scream in agony. Fevenc and his men grabbed their guns and ran to the horse, and came across a "monstrous lizard" burying its claws into the poor animal's shoulders, with its jaws firmly gripped on to its neck. As the horse was frantically trying to kick it off, one man, Murray, fired his rifle at the lizard. Both the horse, which bled to death, and the lizard, were killed, with the lizard's mouth still sunk into the horse. Two men in the party, nicknamed "Dandy" and "Rafter" were both attacked by a second gonderanup, which rafter killed. Unsurprisingly, Favenc and his men immediately gathered all their supplies, hopped on their horses, never to return. Dandy and Rafter both died of their wounds on the way back.
One of the few recorded sightings was In 1931, when Explorer T.C Wollaston reported of an unknown perentie species that is yellow with black spots the size of a coin and averaged at 8 to 15 ft. In the same year, a prospector nicknamed Big Jim reported that while he was fossicking for opals, he came across an enormous 15-17 foot lizard resembling a perentie alarmingly close to him. He tried to ignore it until it made an unusual sound described as “a mix between a lion’s roar and a dog’s bark.” After this, Jim ran away in fear. Later in 1940, explorer Fred Blakeley started an expedition to find the giant perentie and came across footprints and an alleged skin of a 10-foot long perentie killed at Weinikie Gold Field in the Northern Territory.