Alternate casting cost (ACC) or Alternate playing cost (APC) is a term from the card game Magic: The Gathering, and refers to a cost to play a spell that is an alternative to the casting cost in the upper right hand corner of the card. This alternate cost may be some amount of life that its caster pays, some number of cards discarded from the caster's hand, or any number of other drawbacks that can be used to help balance the fact that the card's mana cost does not need to be payed in order to play the card.

Note: This is an informal term. The term used for this in the official rules is "Alternative cost."

Famous cards

Force of Will is the most famous alternate casting cost card, as it has been played extensively in tournaments since it was printed in Alliances in 1996. Its power comes from the way it allows its owner to counter a spell even when they have no untapped mana: it can even be used before the player has taken a turn at all, which means it can disrupt "turn one wins" in tournament formats where they're possible. There are several other alternate casting cost spells which will counter a spell such as Thwart, Foil and Daze, which have also seen play in tournaments, but none of them to the extent of Force of Will. Force of Will was the blue card in a five-card cycle of alternate casting cost cards in Alliances, but none of the others achieved anywhere near the level of recognition that Force of Will did: this is an example of the pattern often repeated in Magic: The Gathering's early years where blue cards were unintentionally printed far more powerful than cards of the other colours.

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Fireblast is a famous red card from Visions which deals four damage to any target. Its mana cost is an expensive six mana, but it can be cast for the alternate cost of sacrificing two mountains. This makes it very strong in aggressive decks with other direct damage spells: once the opponent is down to, say, seven life, the red player could cast a spell to deal three damage which uses all their mana, and then sacrifice two mountains to Fireblast to finish them off.

Misdirection from Mercadian Masques was another blue ACC card. Misdirection lets its caster change the target of an opponent's spell. It saw some play in tournaments.

Gush was yet another powerful blue ACC card, also from Mercadian Masques. It allows its controller to draw two cards for the alternate cost of returning two Islands from play to their hand. This card was so powerful in a tournament deck called Gro-A-Tog that it was restricted to a maximum of one per deck.

Shining Shoal and Sickening Shoal from Betrayers of Kamigawa are alternate casting cost spells with a variable (X) in their cost. Their caster may either set X by paying that much mana, or by removing a card in their hand from the game, which sets X to the converted mana cost of the removed spell. Shining Shoal is a rare example of a white card which can cause damage to be dealt to any creature or player: for this reason it was nicknamed white Fireball. Sickening Shoal is partially renowned for its strange artwork featuring vomiting fish. Other Shoals with the same way of setting X exist for the other colours (the red Blazing Shoal theoretically enables a first-turn win if its player draws two of it as well as certain specific other cards) but Shining Shoal and Sickening Shoal saw the most play in tournaments. Both cards are in the top five most valuable cards from Betrayers of Kamigawa.