Oasis Poker

Oasis Poker (sometimes incorrectly referred to as Caribbean Stud Poker/Caribbean Poker) is derived from classic player vs player poker, but instead the player plays against the house.

Play Structure

Initially the player places an ‘Ante’ wager and the dealer will deal out 5 cards to the player and themselves. All but one of the dealers cards are dealt face down (often referred to as ‘Hole’ cards). The player then has to make the decision to either Fold their hand – losing their Ante wager – discard up to 5 cards or ‘Call’. Where the player chooses to discard cards they will be charged a fee equal to the Ante bet for each card they exchange. This fee is not a bet and will not be returned regardless of the outcome of the hand.  If the player chooses to Call – either before or after discarding cards - they have to place a bet twice the size of the Ante wager then the dealer’s hole cards are revealed and the hands are compared.

Hand Comparison

Oasis Poker ranks hands according to a hierarchy common to poker games which is explained below (strongest to weakest);

* Royal Flush – The Ace, King, Queen, Jack and Ten cards all of the same suit.

* Straight Flush – five numerically adjacent cards of the same suit (Example – 4, 5, 6, 7 and 8 of Diamonds). Where both the player and dealer hold a Straight Flush the hand with the highest card is considered the winner.

* 4 of a Kind – four cards of matching rank (Example - 7 of Hearts, Clubs, Diamonds and Spades). Where both the player and the dealer hold 4 of a Kind the hand with the higher rank is considered the winner.

* Full House – three cards of the same rank and two cards of a different but matching rank (Example – 8 of Hearts, Clubs and Diamonds and Jack of Spades and Hearts). Where both the player and dealer hold a Full House, the hand with the higher rank 3 of a Kind is considered the winner.

* Flush – five cards of the same suit (Example – Ace, 8, 5, 2 and Queen of Spades). Where both the player and dealer hold a Flush the hand with the highest card is considered the winner. Where the highest card is matched the second highest is consider and so on.

* Straight – five numerically adjacent cards ignoring suit (Example – 7 of Spades, 8 of Spades, 9 of Clubs, 10 of Diamonds and Jack of Diamonds). Where both the player and dealer hold a Straight the hand with the highest card is considered the winner.

* 3 of a Kind – three cards of the same rank with 2 unmatched cards (Example – 9 of Spades, Clubs and Hearts with any two other cards that are not the 9 of Diamonds or a matching pair). Where both the player and dealer hold a 3 of a Kind, the hand with the higher ranked 3 of a Kind is considered the winner.

* Two Pairs – two sets of two cards of matching rank with one unmatched card (Example – 4 of Clubs and Hearts, 8 Clubs and Spades and a fifth unmatched card). Where the player and dealer both have two pairs, the hand with the highest pair is considered the winner. If both hands have matching top pair, the higher of the two lower pairs is considered the winner. Where both pairs are matched, the hand with the higher ‘Kicker’ (final unmatched card) is considered the winner.

* Pair - two cards of matching rank with three unmatched card (Example – 6 of Clubs and Hearts and any three other cards that are not the six of Spades or Diamonds and are not of matching rank). Where the player and the dealer hold a matching pair, the hand with the highest Kicker card wins. If the Kicker also matches, the hand is decided by the second Kicker then the third if the second Kickers also match.

* High Card – any five unmatched cards ranked as the highest card (Example – 5 of Spades, 9 of Clubs, 7 of Clubs, 2 of Hearts and Ace of Diamonds would be considered ‘Ace High’).

In the instance where both the dealer and player have hands of matching value by the above table the hand is considered a push and the player’s bets are returned.

Payouts

As with many other poker based casino games, there is a qualification hand for the dealer to play. As such payouts vary depending on whether the dealer qualifies or not. The dealer qualifies if their hand is Ace/King or better.

If the player loses all bets placed are lost. If the player Folds they lose their Ante bet. If the player wins payouts are decided as follows;

* If the player wins and the dealer does not qualify the Ante bet is paid out at 1 to 1 while the Call bet pushes.

* If the player wins and the dealer does qualify the Ante bet is paid at 1 to 1 and the Call bets is paid according to the following paytable;

HANDGAMESYS PAYOUT*PAYOUT
Royal Flush100 to 1100 to 1
Straight Flush50 to 150 to 1
Four of a Kind26 to 120 to 1
Full House8 to 17 to 1
Flush5 to 15 to 1
Straight4 to 14 to 1
Three of a Kind3 to 13 to 1
Two Pairs2 to 12 to 1
Pair1 to 11 to 1
Ace/King1 to 11 to 1
House EdgeXXX0.47%

* This paytable is only used on the ‘Without House Edge’ version of Oasis Poker. It should be noted that when playing the Without House Edge games that the house take a 10% cut of any winnings at the end of the session.

Alternative Discard Rules

Galewind software offer an alternative discard rule. Instead of being charged a full Ante bet for each card discarded the charges for discarding different numbers of cards are as follows;

NUMBER OF CARDS DISCARDED COST
11xAnte
22xAnte
33xAnte
42xAnte
51xAnte

With this rule Galewind software also make an adjustment to the Call bet paytable;

HANDPAYOUT
Royal Flush100 to 1
Straight Flush50 to 1
Four of a Kind20 to 1
Full House6 to 1
Flush5 to 1
Straight4 to 1
Three of a Kind3 to 1
Two Pairs2 to 1
Pair1 to 1
Ace/King1 to 1
House Edge0.55%

Jackpot Bet

The GameSys, GamesOS and Galewind software Oasis Poker games also offer a side bet referred to simply as the ‘Jackpot’ bet. This side bet is optional but if the player chooses to place the Jackpot bet it costs $1 and the results are based only on the player’s final hand (after any dicard/replacements). The payouts for the Jackpot bet are provided below;

HANDHAND PROBABILITIES GAMESYS* GAMESOSGALEWIND
Royal Flush0.0000015390810001000Jackpot
Straight Flush0.000013851750050010% of Jackpot
Four of a Kind0.00024200200500
Full House0.00144170100100
Flush0.0019654506050
Straight0.0039246464040
3 of a Kind0.02112845125
Jackpot Range NANA25000-110280*
Break Even Value NANA218009.7
House Edge 3.05%51.69%31.50%-56.44%*

* This paytable is used for both the normal and ‘Without House Edge’ versions of Oasis Poker at GameSys casinos.

**The Galewind website lists the theoretical minimum House Edge for the Jackpot bet as 24.04% which would equate to a Jackpot size of $135793.56. Our Jackpot range is based on the reset value and the maximum value we’ve seen.

Calculating the House Edge and Break Even value for the Jackpot Bet

It is possible calculate the House Edge and break even value for any jackpot value at the Galewind game simply by using the Hand Probability figures.

To calculate the House Edge we multiply the Paytable values by the probabilities, sum the results and subtract the remaining possibilities. So if we have a Jackpot value of 94000 the calculation would be as follows;

94000x0.00000153908 +  9400x0.0000138517 + 500x0.00024 + 100x0.001441 + 50x0.0019654 – (1-(0.00000153908 + 0.0000138517 + 0.00024 + 0.001441 + 0.0019654+))

0.14467352 + 0.13020598 + 0.12 + 0.1441 + 0.09827 – (1 – 0.00169639)

0.4309795 - 0.9998303609 = -0.3626

So the House Edge for this Jackpot size is 36.26%

House Edge*

The House Edge of Oasis Poker using the standard paytable and across the full round of wagering (Ante bet, Discard fees and Call bet) and assuming that the player plays using the optimal strategy discussed below is 0.47% and Net Entertainment casinos and 0.55% at Galewind casinos. If the player does not play optimally this figure will rise.

The House Edge of the Jackpot bet is dependent on the paytable the casino is using and the size of the Jackpot, but our observations places the House Edge value between 31.50% and 56.44%.

For further information regarding the house edge for both the main game and the Jackpot bet see Beating Bonuses (http://www.beatingbonuses.com/oasis.htm).


Optimal Strategy

The most important aspect of correct strategy while playing Oasis Poker is not to play the Jackpot side bet unless it is over the breakeven values listed above. As the Jackpot theoretically should never exceed the breakeven point this means the player should never play the Jackpot bet. Even if the Jackpot value was above the breakeven value you should be aware that this bet has an extremely high variance and it’s highly unlikely that the regular player will ever hit the Jackpot, meaning that realistically the regular player will be playing with a far higher house edge.

The Optimal Strategy for Discard decisions when playing Oasis Poker is relatively straight forward. Unlike Video Poker games the fee for replacing cards makes discarding a poor choice except in a small number of situations, namely;

- When the player holds four cards of a Royal or Straight Flush and their hand is not a Straight or a Flush. (Discard the one non-Royal/Straight Flush card)

- When the player holds four cards of a Flush and does not have a Pair. (Discard the one non-Flush card)

- When the player holds four cards to an Outside Straight* and does not have a Pair. (Discard the one non-Straight card)

This strategy can be improved on with a little added complexity be discarding;

- When the player holds four to a Flush with a 22 through 66 pair and the dealer’s upcard is of higher rank than the pair. (Discard the one non-Flush card)

- When the player holds four to an Outside Straight* with a 22 or 33 pair and the dealer’s upcard is of higher rank than any cards the player holds. (Discard the one non-Straight card)

- When the player holds four to an Inside Straight* without a pair and the highest card of the Straight is 10 or more with the dealer’s upcard of lower rank than any card in the Straight.

* An ‘Outside’ Straight is four cards that are numerically adjacent meaning that two different cards would create a Straight (i.e. 6, 7, 8, 9). An ‘Inside’ Straight would be four cards that could make a Straight with a gap in between meaning only one card rank could complete the Straight (i.e. 3, 4, 6, 7).

The above is only the strategy for the Discard decision.

For the Fold/Call decision the decisions are similar to Caribbean Stub Poker and as such are too complex for all but the most dedicated player to memorise. A simplified version of this strategy would see the player Call with any hand of Ace/King/Jack/8/3 or better. This results in a house edge 0.1% higher than the full optimum strategy.

Winning Strategies

Offline

Hole Carding, Steering or Sorting

Unlike Blackjack the techniques used to gain an advantage over the game of Caribbean Stud Poker in the offline environment are not nearly so widely discussed. Gaining information on dealer’s hole cards – be that via edge sorting, steering or hold carding – can produce a player advantage as long as the information is used to alter the player’s strategy. Even with information on up to two of the dealer’s hole cards and an optimised strategy the player still has a substantial disadvantage (nearly 2%) so you need to have knowledge of at least 3 of the dealer’s hole cards before this is a worthwhile game. With perfect knowledge of all four dealer hole cards the strategy is trivial – Call, any winning hand or hand where the dealer will not qualify – though it may be worth playing some losing hands to avoid unusual/suspicious folding decisions where you hold a strong hand. With knowledge of only three hole cards or imperfect knowledge of four cards the strategy is more complex.

The rarity of being able to obtain information on 3 or more of the dealer’s hole cards and the high skill level involved ensure that only the most diligent of professional players are ever likely to come across this information and it should be emphasized that the risks involved in gaining less than perfect information are likely to be substantial.

The best source of information on how best to play with additional information can be found in James Grosjean’s ‘Exhibit CAA: Beyond Counting’.  The author provides the full and correct Optimal Strategy for Caribbean Stud Poker for each of the different scenarios where additional information can be gathered. This book is widely considered the Bible for the professional player and as such is not a worthwhile investment for anyone other than a full time professional Advantage Player (not to mention it requires a professional reference to obtain).

Optimum Strategy and Sharing Hand Information

Offline the rules of Oasis Poker prohibit players sharing information about their hands. Online it’s certainly possible to share hand information if a multi-player tables could be found without the online casino being aware of it. However given the prohibited nature of this activity in the offline game we would not like to comment on the ethics of engaging in such activities. As such the following information is for use at the player’s own risk – we do not encourage players to share information while playing Oasis Poker. We’re also not aware of any multi-player options in the online environment and include this information simply due to the easy modification from Caribbean Stud Poker.

While the House Edge of Caribbean Stud Poker cannot be reduced enough to give a player advantage without more hands being played than we are aware of being available online (at least 7 hands), given that the Discard decision substantially reduces the overall House Edge of the game, it may be possible to gain a Player Edge at Oasis Poker if enough additional hands are known.

According to James Grosjean you would need to have information on a full 7 hands and the dealer’s up card (36 cards in total) alongside a playing strategy optomized to the additional information to gain an edge of 2.374% over the house. 6 or less hands and the house retains the edge. Even with complete information the strategy required to obtain this edge is far too complicated for human application. Grosjean has developed a count system that couple be feasibly applied by a team of human players that achieves a player advantage of 1.34%. We have neither the desire, the inclination, nor the permission to republish the details of this count system, but interested parties should look to get hold of Grosjean’s book ‘Exhibit CAA: Beyond Counting’. It should be stated that the opportunities for application of this system are extremely rare and very likely not worth the effort for anyone but the most dedicated professional player.

Online

There are several methods of legitimately gaining an advantage playing online Oasis Poker games. By and large these involve the use of promotions, bonuses and comp point systems as the games by themselves – assuming the game is functioning in a correct fashion and there are no errors in the paytable – will not provide any additional information about the cards and shuffles after every hand.

It should be noted that online advantage play is not specific to Oasis Poker and in recent years the wagering requirements for player’s choosing to play any table game has inflated to the point that Oasis Poker is now often a sub-optimal choice for the player. For more information on beating online casinos see BeatingBonuses.com.

References

James Grosjean ‘Exhibit CAA: Beyond Counting’

* All ‘House Edge’ figures in this article are based on the ‘loss per unit wagered’ rather than ‘loss per initial bet’.