Thunder Boost

Thunder Boost (サンダーアップ) 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 Yellow Opera card, costs 20 CP to add to your deck, and lasts for one reload, while in Kingdom Hearts II, it requires 5 AP to equip, and in Kingdom Hearts Birth by Sleep, up to three copies of it can be equipped.

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

 * The Yellow Opera card has "Thunder Boost" as its ability.

Kingdom Hearts II

 * Sora learns Thunder Boost at level 41 with the Dream Rod, 53 with the Dream Sword, and 99 with the Dream Shield.
 * Donald learns Thunder Boost after freezing the computers at the Dataspace.
 * Jack Skellington has Thunder Boost as a default ability.
 * Tron learns Thunder Boost after downloading the MCP-killer program
 * The Photon Debugger has Thunder Boost as its Equipment Ability.

Kingdom Hearts II Final Mix

 * Sora learns Thunder Boost at level 41 with the Dream Rod, 53 with the Dream Sword, and 99 with the Dream Shield.
 * Donald learns Thunder Boost after freezing the computers at the Dataspace.
 * Jack Skellington has Thunder Boost as a default ability.
 * Tron learns Thunder Boost after downloading the MCP-killer program
 * The Photon Debugger has Thunder Boost as its Equipment Ability.
 * The Meteor Staff has Thunder Boost as its Equipment Ability.
 * The Shock Charm+ has Thunder Boost as its Equipment Ability.

Kingdom Hearts Birth by Sleep

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