A rare cannon crafted by mages. Only its creators know the arcane principles by which it fires.
Final Fantasy Tactics A2: Grimoire of the Rift description
Max Ray is a weapon for Barret, providing 97 Attack, 98 Atk%, 30 Magic, is Long Range, and has three linked materia slots with Normal growth. It can be found as treasure in Midgar during the Raid on Midgar, in the area before the subway. If missed, it can never be obtained again.
Supernal Ray is a low-ranked hand-cannon that provides 25 Attack and 7 Range. It teaches the abilities Foresight for 150 AP to the Cannoneer and Charged Attacks for 150 AP to the Flintlock. It can be obtained from the Bazaar from the "Forgotten Firearms D" category.