It is vital to remember that you use exactly two of your four hole cards to build the best possible five-card hand in Omaha! For example, if you are dealt A♣ A♥ A♠ A♦, you have a pair of Aces and precious few ways to improve your hand. Don’t think a situation like this will ever come up? You’re probably right, but it’s not impossible. The odds of being dealt quads is only 20,824 to 1 against, after all. A friend of ours, who was very new to poker Omaha at the time, received 6♣ 6♥ 6♠ 6♦ as his hole cards, bet all the way to the end, turned over his hand, and announced that he had four Sixes. He was shocked to learn that he only had a full house (there were three Fours on the board to go with his pair of Sixes), but he was relieved when he won the pot anyway!
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The odds of being dealt three of a kind in the hole is a much more reasonable 867 to 1 against, but that’s the end of the good news. When you have three of a kind in the hole, your hand is almost as bad as if you had quads in the pocket.
Caution: The possibility of making mistakes like this one reinforces the need to play against a specialized poker program or in free online games before you risk money in a new game.
As an example, suppose you hold A♠ K♦ Q♠ J♥ and the board reads 10♠ 4♣ J♣ Q♦ 6♠. You hold two spades, but there are only two spades on the board, so you can’t create a straight flush or flush. There are no pairs on the board, so you can’t have four of a kind or a full house. The best hand you can create using exactly two of your hole cards and three of the board cards is an Ace-high straight, T♠ J♣ Q♦ K♦ A♠.