Almagest

Almagest is a recurring spell in the Final Fantasy series. It is always an extremely destructive magic used by powerful enemy entities.

Final Fantasy V
Almagest is an extraordinarily powerful Holy-elemental spell that strikes all party members. Exdeath and the superbosses Enuo and Neo Shinryu also have access to this ability, as well as the enemy Hades.

Final Fantasy Tactics
Almagest damages all units within a two-square radius emanating from the point of casting. Only the monsters Behemoth and Ultima Demon have access to the spell, though the former can be recruited into the party via an Orator. This effectively puts the power of Almagest in the player's hand.

Dissidia Final Fantasy
Almagest appears once again as one of Exdeath's HP attacks. It consists of him surrounding himself in a ball of dark energy, and then exploding it after a few seconds. Furthermore, if the player were to get a perfect EX-Burst, Exdeath would use an upgraded version called Neo Almagest, in which Exdeath would throw his opponent into the Void, and then sealing the entrance by crushing it in his hands.

Etymology
Almagest is the name of the ancient book written by the Greek philosopher Ptolemy. It presents an Earth-centered view of the solar system and was accepted as an astronomical authority for over a thousand years. "Almagest" means "The Greatest" in Greek.