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Space Jack

Introduction

Space Jack was a blackjack variant available at the Slotland and Win a Day Internet casinos. I've seen a lot of strange blackjack variants in my 17 years writing about gambling, and Space Jack has got to be the strangest. As of December 2022, Slotland seems to have dropped Space Jack. I do not know if Win a Day still has it.

It should also be emphasized that the jackpot is temptingly big compared to the natural odds of hitting it. This is the case because the jackpot is not triggered by the natural draw of the cards but artificially, behind the scenes.

Rules

The rules are badly stated on the web site, so here is what you need to know.

  1. Four decks of cards are used.
  2. The player places three bets of equal size, from $1 to $20.
  3. The player is dealt three two-card hands, and the dealer has an up card exposed.
  4. Player blackjacks pay 2 to 1 and beat a dealer blackjack.
  5. The European "no peek" rule is followed. This means that if the player doubles, and the dealer gets a blackjack, then the player will lose both the original and doubled portion of his bets.
  6. Initially, the player may stand, hit or double. The one decision shall apply to all three hands!
  7. Blackjacks do not pay immediately. If you choose to hit or double, then it will ruin any blackjacks.
  8. The player may continue to hit as much as he wishes, until he chooses to stand or all three hands bust.
  9. The player may double only after the initial deal.
  10. If the player bets at least $5 on each blackjack hand, for a total bet of $15, and he gets three blackjacks, then he will win a progressive jackpot.
  11. At the time of this writing (Nov. 9, 2014), the jackpot was at $53,383.
  12. Per the casino's own rules, the jackpot is not triggered by the cards but an internal mechanism. Here is a screenshot of how they explain it:
     
     

    Strategy

    Unfortunately, there is no easy way to quantify strategy for this game that I'm aware of. The good news is that most of the time the right play is pretty obvious. For those cases that aren't, you can find the best play by adding the expected value of all options for each hand. The following three tables show the expected value of each player hand by dealer up card for standing, hitting and doubling respectively.

    Expected Values for Standing Expand

    Hard 2 3 4 5 6 7 8 9 10 Ace
    4 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    5 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    6 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    7 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    8 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    9 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    10 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    11 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    12 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    13 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    14 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    15 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    16 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    17 -0.1533 -0.1173 -0.0778 -0.0413 0.0114 -0.1069 -0.3837 -0.4212 -0.4631 -0.6390
    18 0.1207 0.1475 0.1768 0.2029 0.2833 0.4002 0.1052 -0.1835 -0.2396 -0.3782
    19 0.3851 0.4033 0.4221 0.4429 0.4959 0.6166 0.5939 0.2857 -0.0159 -0.1168
    20 0.6392 0.6493 0.6598 0.6723 0.7039 0.7737 0.7918 0.7579 0.4360 0.1447
    21 0.8816 0.8851 0.8881 0.8921 0.9027 0.9262 0.9305 0.9391 0.8108 0.3291
    BJ 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000 2.0000
    12 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    13 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    14 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    15 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    16 -0.2930 -0.2516 -0.2084 -0.1632 -0.1543 -0.4761 -0.5126 -0.5415 -0.5751 -0.7691
    17 -0.1533 -0.1173 -0.0778 -0.0413 0.0114 -0.1069 -0.3837 -0.4212 -0.4631 -0.6390
    18 0.1207 0.1475 0.1768 0.2029 0.2833 0.4002 0.1052 -0.1835 -0.2396 -0.3782
    19 0.3851 0.4033 0.4221 0.4429 0.4959 0.6166 0.5939 0.2857 -0.0159 -0.1168
    20 0.6392 0.6493 0.6598 0.6723 0.7039 0.7737 0.7918 0.7579 0.4360 0.1447
    21 0.8816 0.8851 0.8881 0.8921 0.9027 0.9262 0.9305 0.9391 0.8108 0.3291
     

    Expected Values for Hitting Expand

    Hard 2 3 4 5 6 7 8 9 10 Ace
    4 -0.1153 -0.0824 -0.0474 -0.0087 0.0106 -0.0881 -0.1596 -0.2408 -0.3431 -0.4362
    5 -0.1286 -0.0951 -0.0594 -0.0203 -0.0017 -0.1192 -0.1884 -0.2667 -0.3655 -0.4362
    6 -0.1411 -0.1070 -0.0708 -0.0312 -0.0135 -0.1517 -0.2175 -0.2927 -0.3880 -0.4362
    7 -0.1096 -0.0765 -0.0409 -0.0037 0.0288 -0.0687 -0.2113 -0.2849 -0.3705 -0.4362
    8 -0.0224 0.0078 0.0404 0.0744 0.1146 0.0826 -0.0604 -0.2104 -0.3059 -0.4362
    9 0.0738 0.1010 0.1299 0.1615 0.1957 0.1722 0.0981 -0.0527 -0.2167 -0.4362
    10 0.1819 0.2058 0.2313 0.2592 0.2875 0.2572 0.1977 0.1163 -0.0526 -0.4362
    11 0.2379 0.2602 0.2840 0.3099 0.3334 0.2924 0.2297 0.1581 0.0339 -0.2097
    12 -0.2537 -0.2337 -0.2127 -0.1911 -0.1708 -0.2127 -0.2718 -0.3401 -0.4280 -0.5510
    13 -0.3081 -0.2913 -0.2735 -0.2554 -0.2358 -0.2689 -0.3238 -0.3872 -0.4689 -0.5831
    14 -0.3625 -0.3489 -0.3344 -0.3198 -0.3009 -0.3211 -0.3721 -0.4310 -0.5068 -0.6128
    15 -0.4169 -0.4064 -0.3953 -0.3842 -0.3659 -0.3696 -0.4170 -0.4717 -0.5420 -0.6405
    16 -0.4713 -0.4640 -0.4562 -0.4485 -0.4310 -0.4146 -0.4586 -0.5094 -0.5748 -0.6662
    17 -0.5364 -0.5319 -0.5272 -0.5223 -0.5088 -0.4833 -0.5060 -0.5539 -0.6161 -0.6939
    18 -0.6226 -0.6202 -0.6177 -0.6148 -0.6075 -0.5910 -0.5911 -0.6167 -0.6745 -0.7418
    19 -0.7292 -0.7281 -0.7271 -0.7258 -0.7226 -0.7154 -0.7137 -0.7156 -0.7502 -0.8097
    20 -0.8553 -0.8550 -0.8548 -0.8545 -0.8536 -0.8518 -0.8515 -0.8508 -0.8607 -0.8978
    21 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000 -1.0000
    Soft 2 3 4 5 6 7 8 9 10 Ace
    12 0.0813 0.1033 0.1279 0.1597 0.1856 0.1658 0.0949 -0.0002 -0.1407 -0.3228
    13 0.0461 0.0741 0.1038 0.1366 0.1613 0.1227 0.0538 -0.0380 -0.1729 -0.3482
    14 0.0219 0.0508 0.0815 0.1152 0.1388 0.0798 0.0130 -0.0754 -0.2049 -0.3735
    15 -0.0006 0.0292 0.0608 0.0953 0.1178 0.0373 -0.0273 -0.1124 -0.2365 -0.3985
    16 -0.0215 0.0092 0.0416 0.0769 0.0984 -0.0046 -0.0670 -0.1489 -0.2677 -0.4231
    17 -0.0010 0.0289 0.0610 0.0945 0.1277 0.0540 -0.0736 -0.1494 -0.2577 -0.4327
    18 0.0623 0.0900 0.1198 0.1509 0.1904 0.1710 0.0392 -0.1009 -0.2085 -0.3729
    19 0.1233 0.1490 0.1764 0.2063 0.2395 0.2210 0.1520 0.0073 -0.1569 -0.3126
    20 0.1819 0.2058 0.2313 0.2592 0.2875 0.2572 0.1977 0.1163 -0.0526 -0.2523
    21 0.2379 0.2602 0.2840 0.3099 0.3334 0.2924 0.2297 0.1581 0.0339 -0.2097
     

    Expected Values for DoublingExpand

    Hard 2 3 4 5 6 7 8 9 10 Ace
    4 -0.5860 -0.5032 -0.4168 -0.3264 -0.3086 -0.9523 -1.0252 -1.0830 -1.1501 -1.5381
    5 -0.5860 -0.5032 -0.4168 -0.3264 -0.3086 -0.9523 -1.0252 -1.0830 -1.1501 -1.5381
    6 -0.5645 -0.4826 -0.3967 -0.3076 -0.2831 -0.8955 -1.0054 -1.0645 -1.1329 -1.5181
    7 -0.4364 -0.3592 -0.2772 -0.1951 -0.1393 -0.5902 -0.8508 -0.9539 -1.0296 -1.3980
    8 -0.2056 -0.1362 -0.0627 0.0109 0.0862 -0.1881 -0.4550 -0.7170 -0.8404 -1.1772
    9 0.0599 0.1205 0.1841 0.2502 0.3164 0.1041 -0.0287 -0.3005 -0.5817 -0.9160
    10 0.3578 0.4089 0.4625 0.5184 0.5750 0.3923 0.2847 0.1452 -0.1599 -0.6264
    11 0.4697 0.5177 0.5679 0.6199 0.6667 0.4627 0.3487 0.2289 0.0131 -0.5412
    12 -0.5075 -0.4675 -0.4253 -0.3821 -0.3415 -0.5069 -0.6173 -0.7366 -0.8880 -1.1902
    13 -0.6163 -0.5826 -0.5471 -0.5109 -0.4717 -0.5875 -0.6923 -0.8072 -0.9534 -1.2257
    14 -0.7250 -0.6977 -0.6689 -0.6396 -0.6018 -0.6681 -0.7673 -0.8777 -1.0188 -1.2613
    15 -0.8338 -0.8129 -0.7907 -0.7684 -0.7319 -0.7487 -0.8423 -0.9482 -1.0841 -1.2968
    16 -0.9426 -0.9280 -0.9125 -0.8971 -0.8620 -0.8293 -0.9173 -1.0188 -1.1495 -1.3323
    17 -1.0728 -1.0638 -1.0543 -1.0446 -1.0176 -0.9667 -1.0121 -1.1078 -1.2321 -1.3879
    18 -1.2453 -1.2404 -1.2354 -1.2296 -1.2150 -1.1821 -1.1821 -1.2334 -1.3491 -1.4835
    19 -1.4583 -1.4562 -1.4542 -1.4516 -1.4451 -1.4308 -1.4273 -1.4312 -1.5005 -1.6194
    20 -1.7105 -1.7100 -1.7095 -1.7089 -1.7073 -1.7037 -1.7030 -1.7017 -1.7214 -1.7955
    21 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000 -2.0000
    Soft 2 3 4 5 6 7 8 9 10 Ace
    12 -0.0724 -0.0069 0.0618 0.1328 0.1789 -0.1845 -0.3174 -0.4545 -0.6265 -1.0481
    13 -0.0724 -0.0069 0.0618 0.1328 0.1789 -0.1845 -0.3174 -0.4545 -0.6265 -1.0481
    14 -0.0724 -0.0069 0.0618 0.1328 0.1789 -0.1845 -0.3174 -0.4545 -0.6265 -1.0481
    15 -0.0724 -0.0069 0.0618 0.1328 0.1789 -0.1845 -0.3174 -0.4545 -0.6265 -1.0481
    16 -0.0724 -0.0069 0.0618 0.1328 0.1789 -0.1845 -0.3174 -0.4545 -0.6265 -1.0481
    17 -0.0080 0.0551 0.1221 0.1891 0.2554 -0.0141 -0.2579 -0.3990 -0.5749 -0.9881
    18 0.1185 0.1773 0.2396 0.3018 0.3808 0.2200 -0.0322 -0.2893 -0.4717 -0.8677
    19 0.2406 0.2953 0.3528 0.4126 0.4790 0.3198 0.1933 -0.0727 -0.3685 -0.7470
    20 0.3578 0.4089 0.4625 0.5184 0.5750 0.3923 0.2847 0.1452 -0.1599 -0.6264
    21 0.4697 0.5177 0.5679 0.6199 0.6667 0.4627 0.3487 0.2289 0.0131 -0.5412
     

    Example



    Let's look at the hand pictured on the right as an example. Doubling is clearly an awful decision, so we can narrow down the viable options to hitting and standing. Basic strategy says to hit 12 against 2 and stand 19 against 2. While hitting is right on two out of three hands, it is only marginally right on the two 12s. Meanwhile, standing is by far the right play for the 19. However, enough talk, let's do the math and calculate the expected value (EV) for hitting and standing:

    EV of standing = 2×-0.2930 + 0.3851 = -0.2003
    EV of hitting = 2×-0.2537 - 0.7292 = -1.2366
     

    So, you can expect to lose -0.2003 hands by standing and -1.2366 by hitting. It isn't even close; standing is the better play.

    Action Frequencies

     

    Here is how often each action is taken on the initial two card hands:

    • Stand: 64.15%
    • Hit: 34.11%
    • Double: 1.73%
    • Jackpot (assuming fair game): 0.0089%.
     

    Analysis

     

    Before considering the jackpot, the house advantage in Space Jack is 6.61% of all initial wagers. For example, if the player makes three bets of $10, then he can expected to lose $10 × 3 × 6.61% = $1.98.

    If the cards were dealt fairly for jackpot purposes, then the probability of winning the jackpot with three blackjacks would be 1 in 11,206. Based on a $15 total bet, the value for each $10,000 in the jackpot would be 5.95%. The meter would need to be only $11,117 to reach breakeven. At the minimum jackpot of $50,000 and $15 bet, the player advantage would be 23.13%. At a $100,000 jackpot, it would be 52.88%.

    However, all that is moot because they admit the jackpot is not determined by the random draw of the cards but rather generated randomly, behind the scenes. Nowhere is it disclosed what this probability is.

    Given that the odds of the jackpot are not quantifiable, I would ignore that element to the game and assume a house edge of 6.61%, which is quite high for a table game. Keep in mind the house edge in conventional blackjack is about 0.5%, depending on the specific rules. Draw your own conclusion.

    Blacklist

    I am big on open and honest gambling. Part of that means electronic representations of physical gambling equipment like cards, dice and balls conform to natural probabilities, as if played in real life. By their own admission, Slotland does not trigger the jackpot in card games by the cards themselves. For this reason, Slotland was on my online casino blacklist for years.

    However, in late 2022 we did a fresh review of Slotland and saw they removed the game. In the interests of fairness and redemption, we removed them from the blacklist.