Windburst is a Quickening Concurrence, which is used when five Level 2 Quickenings are used (four in the International version). It deals non-elemental damage to all enemies with a power of 155.
Windburst is an aerial physical HP Attack for Vaan learned at level 36. It requires 30 CP to equip (20 when mastered), 140 AP to master, has Melee High and Ranged High priorities, and has an Absorb effect. It create a crest of wind and summon a tornado that spins in place for a period of time, while the crest can stun the opponent during start-up.