Ultima Cannon

Ultima Cannon (アルテマキャノン) is a technique that appears in Kingdom Hearts II Final Mix and Kingdom Hearts Birth by Sleep. It allows the user to Formchange the Keyblade into a large cannon that launches large spheres of pure energy at the opponent. It is first used by Terra and is passed on to both Terra-Xehanort and Terra's Lingering Will.

Mechanics
In Kingdom Hearts Birth by Sleep, Ultima Cannon is Terra's ultimate Shotlock. It has a maximum level of 6 and max lock of 16. After the first sphere of energy is fired, the player can increase the damage of a second sphere by pressing when prompted. The more accurately the player times their button press, the more powerful the second energy sphere is.

Kingdom Hearts Birth by Sleep

 * Terra obtains Ultima Cannon by completing the Keepers of the Arena mission at the Mirage Arena.

Kingdom Hearts II Final Mix
The inspiration for this move first appeared during Lingering Will's battle in the Keyblade Graveyard. Lingering Will Formchanges its Keyblade into a cannon and fires one sphere of energy that homes in on its target and produces a large explosion. However, the sphere can be deflected back at the Lingering Will.

Kingdom Hearts Birth by Sleep
Terra-Xehanort uses Ultima Cannon, and it cannot be blocked. However, it can be deflected with techniques like Aerial Slam.

Kingdom Hearts III
The Lingering Will uses Ultima Cannon against Terra-Xehanort in the Keyblade Graveyard. Unlike previous appearances, the Ultima Cannon now fires a continuous beam of energy, rather than spherical projectiles.