Lucavi

The Lucavi are a group of demons from Final Fantasy Tactics, who are working in secret under the cover of the Church of Glabados to revive their dead leader Ultima, the High Seraph. There are at least seven Lucavi, though one of them, Elidibus, is not necessarily connected to the other six. Each Lucavi is connected to a shard of auracite, called a Zodiac Stone, which serves as a conduit for that Lucavi to exist in Ivalice. Each Lucavi also has a human host, allowing them to interact with others in Ivalice without drawing attention. The Lucavi are capable of switching between human and demon form via their Zodiac Stone.

All Lucavi return as Espers in other Ivalice games, notably Final Fantasy XII and Final Fantasy Tactics A2: Grimoire of the Rift; though Elidibus is known as his summon Zodiark.

The Identities of the Lucavi

 * Cúchulainn, the Impure, is associated with the Scorpio Holy Stone, and has possessed Cardinal Delacroix.
 * Belias, the Gigas, is associated with the Aries Holy Stone, and has possessed Wiegraf Folles.
 * Zalera, the Death Seraph, is associated with the Gemini Holy Stone, and has possessed Marquis Elmdore.
 * Adrammelech, the Wroth, is associated with the Capricorn Holy Stone, and possesses Dycedarg Beoulve.
 * Hashmal, Bringer of Order, is associated with the Leo Holy Stone and has possessed Folmarv Tengille.
 * Ultima, the High Seraph, is associated with the Virgo Holy Stone. She originally possessed Saint Ajora, but upon his death was stuck within him, and as such the other Lucavi tried to revive her original host and transfer her to a new one, Alma Beoulve.

Underlings
The Lucavi employ many underlings, the most notable of which are the Archaeodaemons and Ultima Demons. Both are of considerable power, and the Ultima Demons can even cast the spell Ultima. During the battles against Ramza, Belias summons Archaeodaemons to help him, while Ultima summons Ultima Demons to help her. In addition, Celia and Lettie, who serve Marquis Elmdore, are really Ultima Demons, and if defeated in human form during the battle with Elmdore, will transform in their demon form, and continue fighting. It is likely that Loffrey is also an Ultima Demon since Ramza felt the same feeling in Loffrey's presence as with Celia and Lettie. Both Archaeodaemons and Ultima Demons were summoned by Folmarv to help the Undead Zalbaag.

The Attempt to Revive Ultima
Ultima is the leader of the Lucavi, but in her absence Hashmal is left to lead the effort to revive her. Ramza runs afoul of the Lucavi by discovering what they're up to, and Ramza is forced to fight and defeat the Lucavi one by one. By the time he catches up to Hashmal, however, he is dangerously close to reviving Ultima due to the countless bloodshed needed for the resurrection to work. Ultimately, Hashmal succeeds by committing suicide to fulfill the ritual. Ramza then battles Ultima, who transforms into a giant skeletal monstrosity mid-battle. This is still not enough, however, and Ultima is destroyed, though the resulting explosion devastates the area, and it appears that Ramza has perished as well. However, Ramza is seen by Orran Durai, so it appears that Ramza managed to survive the Angel of Blood's demise.