Xu'thrar is a location in Lusst'ghaa, sealed and only openable by a Seeing chosen by Ughro'ecna.

Lust from Beyond (Spoilers)[]

The entrance to Xu'thrar

Amanda leads Victor to the gates of Xu'thrar, saying that within lies the technology needed to save Lusst'ghaa. She is unable to open it, but she hopes that Victor can. When he touches the gates, they both receive visions of lauv'abrarc, and that confirms to Amanda that Victor is the one fated to open Xu'thrar.

In truth, Xu'thrar is lauv'abrarc's prison and contains no technology that can save Lusst'ghaa. When lauv'abrarc turned Lusst'ghaa into a land of eternal ecstasy, he ensured the world would never change or evolve, violating the natural order as set forth by the Demiurges. In response, the Demiurges inflicted Lusst'ghaa with cancer, dooming the world. lauv'abrarc attempted to leave Lusst'ghaa to change other worlds into lands of eternal ecstasy, but the Demiurges captured him and locked him within Xu'thrar. Ever since then, lauv'abrarc has been broadcasting psychic messages across the universes, hoping someone would hear them, achieve the power of Ughro'ecna's avatar, and open Xu'thrar, freeing him.

Should the player choose, Victor can fulfill lauv'abrarc's wish and open Xu'thrar at the end of the game.