Flash Step

Flash Step is an ability in Kingdom Hearts II Final Mix and Kingdom Hearts III. It allows the user to unleash a guard-piercing attack on a slightly distant target while keeping up their own guard.

Mechanics
In Kingdom Hearts II Final Mix, Flash Step is an action ability that costs 2 to equip. When equipped, Sora slides forward with his Keyblade held in front with both hands, before stopping with a small jump that brings the Keyblade upward. This allows him to break through an enemy's guard or parry their attack without his own attack being blocked or interrupted, dealing two hits. Physical defenses such as a Large Body's front do not stop the attack either. The range that would activate the attack begins at roughly the distance that Sora would deliver his basic thrust, to just short of the distance of Slide Dash.

In Kingdom Hearts III, Flash Step is an that costs 3  to equip. Like its previous incarnation, it is a two-hit ability that can pierce an enemy's guard, with both a forward and a upwards component. The forward portion of the attack will parry any attacks it comes into contact with as long as they are not unblockable. The upwards portion of the attack does not have the ability to parry, but instead grants Sora a brief period of invulnerability while active. When it connects with an enemy's attack, Sora will usually be sent into his normal Block stance and can follow up with a reprisal if one is equipped. If an attack would normally break Sora's guard, Sora can either Block normally or assume his guard-broken stance depending on both the type of attack being deflected and the precise timing of when Flash Step made contact. Flash Step can be used either in the air or on the ground, and as a combo starter, it will take priority when attacking a distant enemy that is at the same height as Sora.

Kingdom Hearts II Final Mix

 * Sora learns Flash Step after defeating the Prison Keeper.

Kingdom Hearts III

 * Sora learns Flash Step after beating the game.
 * Light Form has Flash Step as a form ability.
 * Dark Form has Flash Step as a form ability.

Notes and references
Blitzspurt