The Ahool is described as a giant bat or flying primate with a wingspan of 10–12 feet, said to haunt the remote valleys and rivers of West Java. Witnesses claim it screeches its name “Ahooool!” while swooping through rainforest canopies at night. First brought to Western attention by cryptozoologist Ivan T. Sanderson in the 1920s, sightings are still occasionally reported by locals and hikers.