The Vile Four are four monsters in the video game, Final Fantasy: Mystic Quest led by the Dark King. Like the Fiends of Chaos, they also drain the energy from the crystals. The earth began to rot, water turned into ice, volcanoes started rumbling, and strong winds blew. The Vile Four are as follows:
- Flamerus Rex, guardian of the crystal of earth
- Ice Golem, guardian of the crystal of water
- Dualhead Hydra, guardian of the crystal of fire
- Pazuzu, guardian of the crystal of wind
After you defeat them, you have to fight their counterparts in Doom Castle.