This is the third installment in the "Mixed Games" series. I have previously written on razz, and I presuppose the knowledge there of making a low hand, what beats what, etc. In this article, I'll provide some starting hands and some basic decision-making as it applies to the variant of Omaha played in mixed games, like HORSE and HOSE.
Omaha is similar to hold'em. There is a flop, a turn, and river card and you play the board to make the best five-card hand. The difference, however, is that you are dealt four hole cards rather than two and you must play exactly two of your hole cards. Thus, you cannot make a flush by playing four board cards and one of your hole cards, for example.
Omaha high/low split is a variant of Omaha in which the best high hand wins half of the pot and the best low hand wins the other half. Now, when a stipulation is placed on the low hand, such as making it qualify as an 8-low or better, then only 8-lows or better qualify to win the low half of the pot and split with the high hand. For ease of reference, I will write O8 (Omaha 8-low or better) to refer to this game. In online mixed games, like HORSE and HOSE, O8 is the variant played.
In any high/low split game the object is to scoop the pot, that is, to win the entire pot. Thus, in choosing a starting hand you need to keep an eye on both its possibility of winning the high half and the low half of the pot. The best starting hand is A-A-2-3 where the aces are of the same suit as the 2 and 3 respectively (such as 
). This hand is powerful because the aces are the best high hand at the table preflop, just as in hold'em, and because the hand has powerful draws to two nut flushes and the nut low hand as well as the second nut low. If a 2 were to hit the board, this hand has the 3 as insurance. If a flush hits, this hand has insurance against two possible flushes. Thus, A-A-2-3 double suited is the very best possible O8 hand. As with this hand, other suited hands are preferable to non-suited hands, but I won't bother commenting on this any further.
Let's consider some other starting hands. A pair of aces is always a good starting hand, but when you start out playing this game, I would recommend that you pitch a simple naked pair of aces with no low drawing possibilities. Thus, I would only recommend playing aces with at least a 2 or 3 kicker regardless of what the fourth card might be (A-A-2-x and A-A-3-x). You can consider playing A-A-4-5, but that would be the limit of the aces that I would recommend for a beginning player. These hands are powerful hands, at least preflop; in Omaha, a lot changes when the flop hits, which I'll discuss below.
Aside from aces, the lowest pair I recommend for beginners is K-K and that only with an A-2 or A-3. Because of the nature of the game, in O8 someone will have an ace going to the flop. If that player has any kind of draw and hangs around, a lone ace on the river is enough to take you down. Since you will be betting in a limit structure, you simply will not be able to bet the drawing player off the hand. Thus, you need an A kicker as insurance or you need to flop a set.
Of the unpaired starting hands, I personally prefer an A-K-2-3, but it is very close between this hand and an A-2-3-4. The former has rather obvious hi/low features, but the latter is also powerful as a scooping hand since you can make a straight. Whatever one's preference, they are both very good starting hands. In fact, you can play any hand that contains an A-2-3, even if the fourth card is a nine (boo-hiss!). Nines are near worthless in O8. J.B. has a nice article explaining why this is the case. The last set of hands I recommend for a beginner are any four cards in the wheel. Thus you can play an A-3-4-5 or a 2-3-4-5.
Now that we have some starting hands, let's move on to actual play. In general, bring it in for a raise. If there is a raise in front of you, consider reraising with any of the playable A-A hands as well as an A-2-3-4 or A-2-K-K (or a 3). Otherwise just call the raise. If you are first in with any of these starting hands, raise. If you were to be playing with decent players, then raising all these hands would not be optimal, but the context we are currently discussing are the low stakes online mixed games. In these games, when you raise, you'll have plenty of callers.
Omaha is a game of the nuts, so if you get a poor flop, it's time to drop the hand. Fold that beautiful starting hand, and don't sweat it. You'll get much better opportunities in the future. For example, let's say you raise preflop with A-2-4-5, and the flop is K-K-2. Be prepared to pitch it. Say you have A-2-3-8 and the flop is 2-T-J. Pitch it. Never pay to draw at running cards, no matter how pretty your hand looked preflop. If you get to see a free card, take it.
If you get a good flop, bet. Say you have A-A-2-4 and the flop was A-3-T. Bet away. You have a powerful high hand. Hands that call you here will be far behind your set. More than likely, hands that call will have the low draw. You have the nut low draw and the nut high hand. Do not slow play at these levels. Let's say the flop is not so great but still pretty good. You have 
. You opened for a raise in middle position, the button, and both blinds called. The flop is: 
. You don't have a made hand, but you do have the best two draws. Betting gets more money into the pot while you are easily the favorite. Worse draws on both the low and high end will call.
If the situation is reduced further, say to only one draw, then I would still bet if checked to and call one bet if someone leads into you. For example, you raised preflop with A-2-3-J and were called by four players. The flop is T-5-7. You only have the low draw, but pot odds are likely good with the preflop action so you can call if bet into, but you will need to improve on the turn.
Let's consider turn play, starting with the above hand. The best card that can hit for you here is not a 4 but rather an ace. Why is this? An ace makes the nut low for you and also a high hand. Your high hand won't be that great, but if the other players were all on low draws, you might take that half of the pot along with whatever your share of the low half is. In addition, a lot of players will play just a naked A-2 here and that ace will counterfeit their hands. Your J kicker may also be enough to beat whatever trash kickers they have. If you miss the turn, I'd pitch the hand unless the pot odds are just overwhelming, which only happens when numerous players are still playing the pot (this will happen at the lower HORSE levels).
If you bet out with a good drawing hand on the flop (such as the one above with the nut draws to both the low and the flush), I'd bet again on the turn if I still had the two draws. If I had lost one of the draws (my low draw was counterfeited, e.g.), then I would slow down and hope for a free card. If there is a bet, then you will need to calculate your pot odds to see if half the pot justifies a call to try and spike your flush or your low draw.
When you have a powerful made hand, such as the set of aces with a low draw above, continue betting on all safe cards. If there was a flush draw on the flop and it got there on the turn, check behind if given the opportunity. I would call a bet if someone else leads, since you would still have a redraw to the full house and to the nut low.
Rivers are fairly simple. Most of the time, you will have a made hand or a bust. Fold the busts; do not bluff, no one is folding at this level. Deciding whether to bet, raise, or just call a bet on the river is a judgment call based on the read you have on your opponent. When you start out, you may just want to focus on calling any bets rather than raising until you get a better read on opponents. If you have the nut high hand, bet away. If you have the nut low hand, however, I would be a bit more cautious, since this is easily duplicated by other players, which will get you quartered. If the action suggests that the other players in the hand have high hands, then jam the pot as much as you can.
Ultimate Bet and PokerStars have mixed games running throughout the day. Hop in and start developing your O8 skills.