This game is based on the poker game commonly known as 'Omaha High'.

 
Each game begins with 21 cards being dealt face down from one randomly shuffled pack. 16 of the 21 cards are grouped in fours to form 4 separate hands as displayed on the site (these cards grouped in fours can be known as 'hole cards'). The remaining 5 cards form a pool of community cards.

 
The first round of betting occurs whilst all cards are face down (The "deal"). Players should bet on which individual hand they think will win the game. Bets can be placed to back or lay each hand.

 
Each round of betting lasts for a specific period of time before unmatched bets are cancelled and the next cards turned face up. The length of time is indicated by the movement of the bar just below the community cards. (Please note the progress bar is an indication only).

 
At the end of the first round of betting, unmatched bets are cancelled and the hands of four of cards forming the individual hands are simultaneously turned face up. There is then another round of betting, again bets can back or lay each individual hand within the game (Pre Flop).

 
At the end of the second round of betting, unmatched bets are cancelled and the first three of the community cards (sometimes known as the 'flop') are turned face up. Another round of betting then begins.

 
The end of the third round of betting sees unmatched bets cancelled before the fourth card from the community cards is turned face up (this card is sometimes know as the 'turn'). Another round of betting then commences.

 
The fourth and final round of betting finishes with unmatched bets cancelled before the fifth and final of the community cards is turned face up (this is sometimes known as the 'river').

 
The result of the game is determined by which hand is best within the predetermined rank system. Should two hands be of equal standing then dead heat rules will apply. Each hand must consist of two hole cards and three community cards. 
The rank system that determines the winning hand is as follows with the highest first:Royal Flush: Ace, King, Queen, Jack, Ten of the same suit. 
Straight Flush: Straight with all five cards in the same suit. 
Four of a Kind: Four cards of the same number or face value ('quads'). 
Full House: Three cards of one number or face value and two cards of another number or face value. If more than one player has a full house, the full house with the highest ranking three of a kind ('trips') wins. 
Flush: Five cards of the same suit. If there is more than one flush, the hand with the highest card(s) wins. 
Straight: Five cards in sequence. Cards can be in any suit. An Ace can be used in the highest straight (10, J, Q, K, A) and the lowest straight (A, 2, 3, 4, 5). If there is more than one straight, the hand with the highest card in the straight wins. 
Three of a Kind: Three cards of the same number or face value ('trips'). 
Two Pair: If two players have two pair, the hand with the highest pair wins. If they have the same high pair, whoever has the second highest pair wins. If they have the same two pair, whoever has the highest fifth card ('kicker') wins 
One Pair: Two cards of the same number or face value. If two players have the same pair, the highest outside card(s) wins. 
High Card: The hand with the highest card(s) wins. 


 
Should two or more hands have cards or combinations of cards with equal standing and value then the value of the remaining cards in that hand is used to determine the winner (sometimes known as the kicker). Should one or more hands still be of equal value then dead heat rules will apply to the winning hands (sometimes known as 'splitting the pot').

 
Betting Selections 
In Exchange Omaha Hi, there are two markets which are available for betting for any given Omaha Hi game. The two markets each hold different types of betting selections. The first market is known as the main market and contains the betting selections for the Game Outcome, i.e. Hand 1, Hand 2, Hand 3 and Hand 4. This market is known as a ‘Win Only Market’ and generally only a single selection will win (however it is possible for a dead heat to occur when the winning selections will be settled according to the dead heat rules). The Side bets market is also a ‘Win Only Market’, however for this market each of the selections are mutually exclusive and therefore one of the selections will win, and the other selections will be settled as losers. It’s also important to note that the main and side bets markets are two separate markets with commission on each charged at according to the standard Betfair commission charging model.

 
The side bets selections are as follows:

Winner has a Full House or better - Will the winning hand(s) have a Full House or better?

If the winning hand(s) has a Full House then this selection wins
If the winning hand(s) has a Four-of-a-Kind then this selection wins
If the winning hand(s) has a Straight Flush then this selection wins
If the winning hand(s) has a Royal Flush then this selection wins
If the winning hand(s) has a Flush then this selection loses

Winner has a Flush - Will the winning hand(s) have a Flush?

If the winning hand(s) has a Flush then this selection wins
If the winning hand(s) has a Straight Flush then this selection loses
If the winning hand(s) has a Royal Flush then this selection loses

Winner has a Straight - Will the winning hand(s) have a Straight?

If the winning hand(s) has a Straight then this selection wins
If the winning hand(s) has a Straight Flush then this selection loses
If the winning hand(s) has a Royal Flush then this selection loses


Winner has a Three-of-a-Kind - Will the winning hand(s) have Three-of-a-Kind?

If the winning hand(s) has a Three-of-a-Kind then this selection wins
If the winning hand(s) has a Full House then this selection loses
If the winning hand(s) has a Four-of-a-Kind then this selection loses

Winner has a Two pair or worse - Will the winning hand(s) have Two Pair or less?

If the winning hand(s) has Two Pair then this selection wins
If the winning hand(s) has One Pair then this selection wins
If the winning hand(s) has No Pair, High Card then this selections wins
If the winning hand(s) has a Full House then this selection loses
If the winning hand(s) has a Four-of-a-Kind then this selection loses