Casinos have turned the popular children's card game of war into a betting game for adults. The object is to have a higher card than your opponent — in this case, the dealer. Casino war is usually played with six decks of cards, which are ranked the same as in poker, except that the ace is always high. As in Acey Deucy, suits don't matter.

To play casino war, you make an initial bet, and you and the dealer each get one card, face-up. If your card is higher than the dealer's, you win even money. If it's lower, you lose your bet. If you and the dealer have the same card, you have two choices: you can surrender, in which case you forfeit half your bet, or you can go to war. If you decide to go to war, you have to place an additional bet equal to your original bet. (At some casinos, the dealer may do the same, but only for show; it doesn't change the payout.) After you place the war wager, the dealer will burn, or discard, three cards and give you and himself another card.

If you beat the dealer on the second card, your raise bet gets even money, and your original bet is a push, which the dealer returns to you. If the dealer's second card is higher than your second card, you lose both your original bet and your raise. Some casinos offer a bonus on the raise bet if the second cards tie. Typically, you get a 2:1 bonus on your raise, and your original bet is a push. Some casinos give you a 3:1 payout on the raise but you forfeit your original bet. Either way, you end up with the same amount.

The house edge on casino war varies with the number of decks used and the bonus structure. A straight six-deck game with no bonus offering carries a house edge of about 2.8 percent. If the casino offers bonuses on second-card ties, the house edge drops to about 2.3 percent.