Reaction Boost (リアクションアップ, Riakushon Appu, lit. "Reaction Up") is an ability that appears in Kingdom Hearts II. It allows the user to deal more damage with Reaction Commands.

Mechanics

In Kingdom Hearts II, Reaction Boost is a support ability that costs 2 AP to equip. It multiplies the damage dealt with Reaction Commands and Jump by 1.5 (2 when 2 copies are equipped). It has no effect on Limits.

Learning Reaction Boost

Kingdom Hearts II

• Roxas learns Reaction Boost at the beginning of the Third Day in Critical Mode.^{[KH II FM]}
• Sora learns Reaction Boost at level 15 with the Dream Sword, 23 with the Dream Shield, and 33 with the Dream Rod.
• The Guardian Soul has Reaction Boost as its equipment ability.

• Kingdom Hearts II abilities