Omaha

Q: What is a successful Omaha strategy?
A: See every flop and get lucky!

Ok, it’s a good joke, but there’s considerably more to playing Omaha than that...
Omaha is a game of big pots and big hands. Whereas in Hold’em two pair or three of a kind often constitute strong hands, when it comes to Omaha these hands are likely to get you into trouble. At a full table you’ll probably need a stronger hand to win – straights, flushes, full houses...
 
Since Omaha is played with four hole cards a hand contains six Hold'em hands when the four cards are converted to all possible combinations of two. ie: ABCD = AB, AC, AD, BC, BD, CD.

(Players must play two cards from their hands and three from the board). If you are in a pot with five other players after the flop, this is comparable to a Texas Hold'em game against thirty other players, because each of your five opponents is holding six Hold'em hands instead of one.
If you get down to the river with a strong hand, but one which can be beaten by some other two card combinations, brace yourself for a loss!
Your high-end straight on the flop runs into serious problems when the board turns up three suited cards or a pair, because a flush or a full house will usually pop up to beat you - in Omaha, always play for the NUTS!

With four cards to choose from, you’ll probably have what, in hold’em, would be regarded as at least one decent starting hand – but so will everyone else. Such hands are as common as sand on a beach and Omaha games normally have more players and bigger pots than in hold'em.
To ensure those bigger pots move in your direction, select starting hands containing four cards which all interact with each other to make the equivalent of five or six decent hold'em hands instead of only one or two. You will see a few exceptions to this here in the starting hands strategy.

Definitions

High Cards - A, K, Q, J, 10
Middle Cards - 9, 8, 7, 6
Low Cards - 5, 4, 3, 2
Suited Hand - Two of the player’s four cards are of the same suit.
Double Suited Hand - Two of the player’s cards are of one suit and two of another suit.
Active Sidecard – A side-card which, when combined with another, makes two parts of a straight or flush.
Nut Hand - An unbeatable high or low hand, sometimes called a "lock".
Set - Three of a kind with two of the three in your hand.
Trips - Three of a kind with all or two of the three on the board.
Rainbow - Hand or flop with cards of all different suits.
Fast Play - Bet, raise and re-raise to get as many other players out as possible.
Slow Play - Just check or call along to keep other players in the game to increase the pot odds.
Check-fold - Check when you can and fold if you are bet into, gladly accepting all free cards offered.

  
Your decision as to whether to play or fold a hand should be based on an assessment of the hand type and the six hold'em hands in your four-card Omaha hand.

Two Card Hold'em Hands To Look For In Omaha Hands:

Premium Hands

High pair – A-A, K-K, Q-Q, J-J, 10-10.
Ace and high card suited – A-K(s), A-Q(s), A-J(s), A-10(s).

Strong Hands

High cards suited – K-Q(s), K-J(s), K-10(s), Q-J(s), Q-10(s), J-10(s).
Middle pairs – 9-9, 8-8, 7-7, 6-6.
Two high cards – A-K, A-Q, A-J, A-10, K-Q, K-J, K-10, Q-J, Q-10, J-10.
Ace and middle card suited – A-9(s), A-8(s), A-7(s) A-6(s).
Middle suited connectors – 10-9(s), 9-8(s), 8-7(s), 7-6(s).

Minimum Hands

Low pairs – 5-5, 4-4, 3-3, 2-2.
Ace and low card suited – A-5(s), A-4(s), A-3(s), A-2(s).
Any two cards to a straight – e.g. 10-6, 9-8, 7-5, 7-3, A-4.
(These kinds of hands are often unplayable in hold’em, but add value in combination Omaha hands.

Unplayable Starting Hands

These hands should be automatically folded without any further consideration:
Quads - (including) A-A-A-A.
Trips - (except A-A-A with a high, suited side-card, this is sometimes playable).

Playable Omaha Starting Hands

Pair of aces – A-A-x-x.
Pair of kings – K-K-x-x.
High pair with ace suited – Qh-Qs-Ah-x .. Jh-Js-Ad-6d.
High pair with middle/low pair – J-J-7-7 .. Q-Q-4-4.
High pair with two or more other hands – J-J-9-7 .. K-10-10-8
Any four high cards – K-Q-J-10 .. A-K-J-10 .. Q-Q-10-10 .. A-J-J-10 .. (includes two high pairs).
Three high cards with ace suited – Ah-Qs-10h-x .. Ah-Ks-Jd-5h.
Three high cards with active sidecard – K-Q-J-8 .. Ah-Qs-10d-4h.
Three card straight with a pair  - 7-6-5-5 .. 9-8-7-8.
Three card straight with ace suited - 8h-7s-6d-Ah .. Ah-9s-8d-7h.
Close group with two gaps or less – J-10-7-6 .. 8-7-6-5 .. 9-8-5-4.. 9-7-6-4 .. J-10-8-6.

Basic strategy tips

• Always be aware of the nut hand possibilities.
  As the board develops, make sure you always know what the three best hand possibilities are, and how that might change on the next card.

• A high pair with an overcard is a good flop in hold'em - but not in Omaha.
  In this game you need to flop AT LEAST two pair, a set, or better.

• Don't raise before the flop generally, unless you are holding Aces or Kings and are in position to narrow the field. Another time to raise is when you are unraised on the button and have a strong hand. Try not to let the blinds play bad hands cheaply.

• Fold your straight draw if that's all you have and you don't flop an unpaired rainbow. If you do get the right kind of flop, bet/raise to discourage the back door flush draws.

• Don't overvalue low pairs. A pair of fours in your starting hand is useless unless it flops a set – and even then a low set on the flop is not a very strong hand in Omaha.

• Study your opponents, especially when you are not playing hands and can pay careful attention. Do they find more hands to play than they fold? Do they bluff? Can they be bluffed? Do they have any "tells" (give away mannerisms) in their betting patterns which disclose information about their hands?

• Get caught bluffing once in a while – it’s a way to vary your play and not be too predictable. You lose a few chips this way, but it will get you calls from weaker hands down the line when you have a strong hand and need the action.