The Mystery of Mount Fang

This is a vanilla-compatible four map mini WAD titled "The Mystery of Mount Fang". After enjoying your "vacation", you're hired by an anonymous benefactor to go hiking in Mount Fang, a huge mountain located in Hell. Your mission: To gather information and clues about about a long extinct civilisation that apparently worshipped a guardian spirit taking on the appearance of a huge shark. But you have a suspicion that the thing who hired you knows more about this place than they let on...