Thunder Boost

Thunder Boost (ファイアアップ, Faia Appu, lit. "Thunder Up") is an ability that appears in Kingdom Hearts: Chain of Memories, Kingdom Hearts II, and Kingdom Hearts Birth by Sleep. It increases the damage done by Thunder-based attacks. In Kingdom Hearts: Chain of Memories, "Thunder Boost" is activated by the Red Nocturne card, costs 20 CP to add to your deck, and lasts for 1 reload, while in Kingdom Hearts II, it requires 3 AP to equip, and in Kingdom Hearts Birth by Sleep, up to three copies of it can be equipped.

Learning Thunder Boost

Kingdom Hearts: Chain of Memories and Kingdom Hearts Re:Chain of Memories

• The Red Nocturne card has "Thunder Boost" as its ability.

Kingdom Hearts II

• Sora learns Thunder Boost at level 15 with the Dream Rod, 23 with the Dream Sword, and 33 with the Dream Shield.
• Donald learns Thunder Boost after defeating Scar.
• Mulan learns Thunder Boost after losing her disguise.
• Jack Skellington has Thunder Boost as a default ability.
• The Bond of Flame has Thunder Boost as its Equipment Ability.

Kingdom Hearts II Final Mix

• Sora learns Thunder Boost at level 15 with the Dream Rod, 23 with the Dream Sword, and 33 with the Dream Shield.
• Donald learns Thunder Boost after defeating Scar.
• Mulan learns Thunder Boost after losing her disguise.
• Jack Skellington has Thunder Boost as a default ability.
• The Bond of Flame has Thunder Boost as its Equipment Ability.
• The Rising Dragon has Thunder Boost as its Equipment Ability.

Kingdom Hearts Birth by Sleep

Thunder Boost can be attached to a type A or type B Command recipe through Command Melding, either randomly or by applying a Shimmering Crystal.