Retrograde

Retrograde (ナンバーリバース) is an ability that appears in Kingdom Hearts: Chain of Memories and Kingdom Hearts Re:Chain of Memories.

Kingdom Hearts: Chain of Memories
Reverses the values of all cards until the deck is reloaded. For example 1 becomes 9, 2 becomes 8, 3 becomes 7, etc. Cards with a value of 0 are not affected.

Kingdom Hearts: Chain of Memories

 * This ability comes from the Powerwild Heartless's Enemy Card. Sora can obtain the Powerwild Enemy card and then use it anytime, whereas Riku automatically obtains the card upon entering Olympus Coliseum, however he can only use it there.