Exdeath's Sealed Cave is an unnamed and unvisitable location in Final Fantasy V. It is located in a x-shaped forest on northwest part of the Eastern Continent in Bartz's World. According to the Warriors of Dawn, the location was chosen to seal the evil warlock due to being the place where the power of the four crystals gathered.
Thirty years before the story, the Warriors of Dawn—Galuf Halm Baldesion, Dorgann Klauser, Kelger Vlondett, and Xezat Matias Surgate—followed Exdeath to the other half of Planet R that was separated to seal the Void. As the warriors were unable to defeat Exdeath, they chose to harness the power of the four crystals of this world to seal the evil warlock within the cave. Feeling responsible, and fearing that Exdeath might one day break free of the seal, Dorgann remained behind in this world to guard the seal, while his friends returned to their original world.
The seal remained unbroken for 30 years, but its power slowly weakened due to the kingdoms having been harnessing the powers of the Wind, Fire, and Water Crystals. Sensing opportunity, Exdeath took control of various important individuals and monsters to speed up the process, leading to the destruction of the four crystals, freeing him from imprisonment.