H.O.R.S.E. is a limit game, and consists of rounds of play cycling among: Texas Hold'em, Omaha eight or
better, Razz, Seven card Stud, and Seven card stud Eight or better.
Refering to the WSOP:
"The winner of the Main Event has traditionally been given the unofficial title of World Champion. However the
game's top professionals have stated that the recently-added $50,000 H.O.R.S.E. event is the one which
ultimately decides the world's best player. H.O.R.S.E. is an event in which Hold 'em, Omaha, Razz, Seven Card
Stud and Eight-or-better are all played. The H.O.R.S.E. tournament was won by Chip Reese in 2006 and
Freddy Deeb in 2007. It should be noted that the professionals played a major role in convincing WSOP
management to stage an event with a much larger buy-in than the Main Event; the growth of poker
tournaments and the World Series (by way of "The Moneymaker Effect") had resulted in fields with a far
greater number of amateurs in proportion to professionals. Hence, the Main Event now has a much greater
likelihood of producing winners who are amateurs and/or relatively unknown players. The professionals sought
to create an event which was far more likely to produce a more well-rounded poker professional as the
eventual winner. The $50,000 buy-in, being five times larger than the buy-in for the Main Event, has thus far
tended to deter amateurs from playing in the H.O.R.S.E. tournament." - Wikipedia
Omaha Eight or Better; each player makes a separate five-card high hand and five-card low hand
(eight-high or lower to qualify), and the pot is split between the high and low (which may be the same player).
To qualify for low, a player must be able to play an 8-7-6-5-4 or lower (this is why it is called "eight-or-better",
or simply "Omaha/8"). Each player can play any two of his four hole cards to make his high hand, and any
two of his four hole cards to make his low hand. If there is no qualifying low hand, the high hand wins (scoops)
the whole pot.
Razz is a form of stud poker that is normally played ace-to-five low. The object of Razz is to make the lowest
possible hand from the seven cards you are dealt. In Razz, straights and flushes do not count against you for
low, and the ace always plays low. The best possible Razz hand is 5-4-3-2-A, or 5 high, also known as "the
wheel".
Seven-Card Stud is a variant of stud poker. Until the recent increase in popularity of Texas hold 'em,
seven-card stud was the most popular poker variant in home games across the United States, and in casinos
in the eastern part of the country. Seven-card stud is also played in western American casinos, but Texas
hold 'em is far more popular there. Two to eight players can play.
Eight-or-Better Seven-Card Stud
Also known as "seven eight" or "stud eight", eight or better is the most common form of high-low split stud.
Played as seven-card stud, but the pot is split between the player with the highest hand and the player with
the lowest hand, which may be the same player). An 8-high hand or lower is required to win low. Betting takes
place as if playing standard high-hand stud; that is, low card pays the bring-in, if any, on the first round, and
subsequent rounds start the betting with the highest showing poker hand. The showdown is cards speak, that
is, there is no declaration for high and low. If there is no qualifying low hand, high hand takes the entire pot.