Dark Impulse (KHBBS)

Dark Impulse (ダークインパルス) is a Level 2 Command Style exclusive to Terra in Kingdom Hearts Birth by Sleep. It is activated by using Zero Gravity-related, Magnet-related, dark, or status-inflicting Deck Commands, by using commands like Zantetsuken, Ars Solum, Limit Storm, Sacrifice, or Warp, or by using a Big Bad Pete.

Kingdom Hearts Birth by Sleep
After visiting Destiny Islands, Terra heads to the Badlands and talks to Master Xehanort. Xehanort tells him that Ventus is going to confront Master Eraqus about his past, and, fearing the worst, Terra goes after Ven.

Upon arriving at the Land of Departure, Terra defends Ven from Eraqus's light attack and refuses to budge in the face of his master's Keyblade assault. When Eraqus uses his light magic to knock the two boys back, Terra summons his darkness and sends Ventus into the Lanes Between. In the ensuing battle with Eraqus, Terra uses his darkness to amplify his attacks.

Mechanics
While using Dark Impulse, Terra's attacks become faster and deal dark damage. The standard four-hit combo deals 180% damage and lifts him off the ground as he barrages them with a fast and furious flurry of Keyblade slashes and clawing attacks from the free hand. The combo finisher ends with Terra materializing a large hand of dark energy, dealing 340% damage to enemies.

The standard combo while attacking is a four-hit combo. The finisher composes of Terra sinking into the ground, homing in on a single enemy and quickly moving under that enemy, and then jumps out of the ground, materializing the hand again straight up into the air, dealing 1050% damage.

Appearance
When using Dark Impulse, Terra gains a dark aura around him and a black light is focused on his left hand. Wisps of darkness emanate from his body as well.

Kingdom Hearts Birth by Sleep

 * Terra learns Dark Impulse after visiting the Keyblade Graveyard a second time.

Kingdom Hearts Birth by Sleep
Once Xehanort is in possession of Terra's body, Terra-Xehanort uses Dark Impulse against Terra's Lingering Will in the Keyblade Graveyard, and against Aqua in the Radiant Garden.