Oasis Poker
Introduction
Oasis Poker is a variation of Caribbean Stud Poker. The rules of Oasis Poker are the same as Caribbean Stud, except the player is allowed to exchange cards before the raise/fold decision, for a price of course. The game can be found mostly in eastern Europe, northern Africa, and Internet casinos using Galewind Software. Following are the complete rules.
Rules
The player makes an ante wager plus optional side bonus side bet.
Player and the dealer get five cards each. All cards are dealt face down, except one dealer card is exposed. The player may examine his own cards but sharing of information is not allowed.
The player has the option to switch one card of his choice for the next card in the deck. There is a fee to do this, equal to the ante wager. This fee is non-refundable.
The player may switch one of more cards. The price for switching depends on the number of cards switched, as follows:
One card: 1x the Ante.
Two cards: 2x the Ante.
Three cards: 3x the Ante.
Four cards: 2x the Ante.
Five cards: 1x the Ante.
If the player switches all five cards, then he must raise.
The player may either fold or raise.
If player folds, then he forfeits his cards, ante bet, and side bet (if made).
If player raises, then he must make a raise wager exactly equal to twice the ante.
The dealer will turn over his other four cards.
The dealer must have an ace/king or higher to qualify. In other words, the lowest qualifying hand would be ace,king,4,3,2.
If the dealer does not qualify then the player will win even money on his ante wager and the raise will push.
If the dealer qualifies and beats the player both ante and raise will lose.
If the dealer qualifies and loses to the player then the ante will pay even money and the raise according to the Raise Pay Table below. Other pay tables have been known to exist. If the player and dealer tie then both the ante and raise will push.
The bonus bet win will be entirely based on the poker value of the player's original hand.
Standard Raise Pay Table
Hand |
Pays |
Royal flush |
100 to 1 |
Straight flush |
50 to 1 |
Four of a kind |
20 to 1 |
Full house |
7 to 1 |
Flush |
5 to 1 |
Straight |
4 to 1 |
Three of a kind |
3 to 1 |
Two pair |
2 to 1 |
All other |
1 to 1 |
Strategy
I have never quantified a perfect card switching strategy. My program makes a perfect decision every time by analyzing all possible combinations of the replacement card and all four dealer cards. However, from running through some test hands I believe the following strategy is close to optimal.
The player should switch one card with any of the following:
Four to a straight flush and royal flush, even breaking up a pair Four to a flush with no pair. Four to an outside straight with no pair.
The player will sometimes switch with any of the following:
Four to a flush with a low pair (depends on the pair and dealer's up card). Four to an inside straight with no pair (depends on the inside straight and dealer's up card).
My apologies for not being more specific. In my view there, is not enough demand for the information to warrant doing a more detailed strategy.
Do not switch with two pair or three of a kind.
If the casino allows switching two or more cards that option should never be taken.
Once the switch decision has been made the player can follow Caribbean Stud Poker strategy when deciding to raise or fold.
Odds
The following return table is based on the pay table above. Other pay tables are known to exist, which would change the odds.
Return Table
Event |
Switch |
Pays |
Combinations |
Probability |
Return |
Player wins with royal flush |
No |
201 |
703909080 |
0.000001 |
0.000169 |
Player wins with straight flush |
No |
101 |
6591048240 |
0.000008 |
0.000795 |
Player wins with four of a kind |
No |
41 |
118962303600 |
0.000142 |
0.005826 |
Player wins with full house |
No |
15 |
698227961760 |
0.000834 |
0.01251 |
Player wins with flush |
No |
11 |
917993591760 |
0.001097 |
0.012062 |
Player wins with straight |
No |
9 |
1839831676200 |
0.002198 |
0.019779 |
Player wins with three of a kind |
No |
7 |
9838202149440 |
0.011751 |
0.08226 |
Player wins with two pair |
No |
5 |
20496509853120 |
0.024482 |
0.122412 |
Player wins with pair or less |
No |
3 |
97623586047960 |
0.116608 |
0.349824 |
Dealer doesn't qualify |
No |
1 |
185955255229464 |
0.222117 |
0.222117 |
Tie |
No |
0 |
12240105192 |
0.000015 |
0 |
Player folds |
No |
-1 |
339591911883840 |
0.40563 |
-0.40563 |
Player loses |
No |
-3 |
109793339508384 |
0.131144 |
-0.393433 |
Player wins with royal flush |
Yes |
200 |
2650657380 |
0.000003 |
0.000633 |
Player wins with straight flush |
Yes |
100 |
24129845136 |
0.000029 |
0.002882 |
Player wins with four of a kind |
Yes |
40 |
0 |
0 |
0 |
Player wins with full house |
Yes |
14 |
0 |
0 |
0 |
Player wins with flush |
Yes |
10 |
3022953154968 |
0.003611 |
0.036108 |
Player wins with straight |
Yes |
8 |
3012064741860 |
0.003598 |
0.028782 |
Player wins with three of a kind |
Yes |
6 |
0 |
0 |
0 |
Player wins with two pair |
Yes |
4 |
0 |
0 |
0 |
Player wins with pair or less |
Yes |
2 |
5747378958780 |
0.006865 |
0.01373 |
Dealer doesn't qualify |
Yes |
0 |
14509998995172 |
0.017332 |
0 |
Tie |
Yes |
-1 |
1981751652 |
0.000002 |
-0.000002 |
Player folds |
Yes |
-2 |
37230605388900 |
0.044471 |
-0.088941 |
Player loses |
Yes |
-4 |
6750562960512 |
0.008063 |
-0.032253 |
Total |
|
|
837195681722400 |
1 |
-0.010372 |
The lower right cell shows a house edge of 1.04%.
After possibly switching and raising, the average final bet, including the switching fee, will be 2.183772 units. The element of risk is thus 0.475%. On average the player will switch 8.4% of the time.
At Internet casinos using Galewind Software there are some rule changes. There the player may switch one to five cards, for the price of one ante per card, and a full house pays 6 instead of 7. Under those rules the house edge is 1.204%, the average final wager is 2.184 units, and the element of risk is 0.55%.
Side Bet
I indicate the odds of the side bet in my Caribbean Stud Poker section. Some casinos have been known to base the side bet on the hand after switching. This can be a very good rule for the player. However, if you see it, you're on your own.
Jackpot Bonus payout
Royal Flush: Jackpot (minimum amount €20,000)
Straight Flush: 20% of the jackpot
Four of a kind: 250 for 1
Full House: 150 for 1
Flush: 100 for 1
Straight: 50 for 1