Speaking of sleights/combos, these occur when 2 or 3 cards are combined into one attack (by pressing L and R Buttons, a card is moved into the holding spot below the Hit Point meter).This also holds true for sleights/combos, which makes 0 cards incredibly valuable to have in a deck. By waiting till an enemy starts their attack, Sora can play the 0 cards to break their card, stopping their attack cold, regardless of what value points their card in play possesses. The only time a lower card can break a higher card is when a 0 card is employed.
If a lower value card is played after a high value card, the lower value card will just bounce away, not having any effect on the battle.If the cards are of equal value, both cards are broken, allowing no attack for that action. The same holds true if Sora is using a card and an enemy uses a higher valued card, they will 'break' Sora's card, stopping his attack. If Sora's card is of higher value than one being used by an enemy, this will stop the enemy's attack, 'breaking' their card.Each time a card is used, an action will occur. Each battle consists of Sora's deck being used against an enemy's deck.
