Ultima Cannon (アルテマキャノン Arutema Kyanon) is a technique Kingdom Hearts Birth by Sleep. Despite this technique being exclusive to Terra. The attack consists of the user transforming their Keyblade into a large cannon, which launches two large balls of energy at the opponent.
Mechanics
In Kingdom Hearts II Final Mix, the Lingering Will's version only fires one ball of energy, though the blast is larger than the Kingdom Hearts Birth By Sleep version, and it homes in on its target.
In Kingdom Hearts Birth by Sleep, Ultima Cannon is Terra's ultimate Shotlock that has a maximum level of 6 and max lock of 16. After the first ball of energy is fired, the player can increase the damage of the second ball by pressing 
when prompted. The better the player times their button press, the more powerful the second energy ball is.
Learning Ultima Cannon
Kingdom Hearts Birth by Sleep
- Terra can obtain Ultima Cannon by completing the Keepers of the Arena mission at the Mirage Arena.
Other appearances
Terra-Xehanort inherits a version of this technique from Terra, and uses it during his boss battle.
The Lingering Will can use a version of this technique as it is an extension of Terra. Template:Section-stub