How to play
Spark 21 is classic six-deck blackjack with a twist on every deal. Before the cards come out, one, two or three spark cards light up, each with a multiplier from ×2 to ×25. Win a hand that holds a spark card and your winnings are multiplied. The sparks aren’t free: every bet carries a fee of 20%.
The aim is the usual one: finish closer to 21 than the dealer without going over. Cards 2 to 10 count their face value, Jacks, Queens and Kings count 10, and an ace counts 1 or 11.
A round:
- Choose a chip and bet between 10 and 500 credits. The message shows the fee next to your bet: a 10 bet costs 12 in all.
- Press Deal. The spark cards for this round appear above your hand, then the cards are dealt.
- If the dealer shows an ace you can take insurance, which costs half your bet and pays 2 to 1 if the dealer has blackjack.
- When the dealer shows an ace or a 10-value card, they check for blackjack before you play.
- Play your hand with Hit, Stand, Double or Split.
- The dealer draws to 17 and stands on every 17. Wins pay even money and blackjack pays 3 to 2, before any multiplier.
Spark cards
A spark card is one exact card, rank and suit: a 7♥ ×5 sparks every Seven of Hearts in the shoe, but not the Seven of Spades. Each round picks new ones:
| Spark cards in a round | Chance |
|---|---|
| One | 55% |
| Two | 33% |
| Three | 12% |
| Multiplier | ×2 | ×3 | ×4 | ×5 | ×8 | ×10 | ×15 | ×25 |
|---|---|---|---|---|---|---|---|---|
| Chance | 30% | 25% | 15% | 12% | 8% | 6% | 3% | 1% |
How the multiplier works:
- Only winning hands. The winnings are multiplied and your bet comes back once. A 10 bet that wins with a ×5 spark card returns 10 + 50.
- Blackjack too. A blackjack pays 3 to 2 and then the multiplier: a 10 bet with an ace of a ×4 spark pays 15 × 4 = 60.
- Multipliers multiply. Two spark cards in one hand, ×5 and ×3, make ×15. The same spark card twice counts twice. The total is capped at ×1,000.
- Doubles and splits. A doubled hand multiplies its whole doubled win. After a split, each hand counts only its own cards.
- Not on pushes or losses. A push gives your bet back, nothing more. Insurance isn’t multiplied.
- Only your cards. Spark cards in the dealer’s hand do nothing.
A spark card in your hand gets a gold frame and its multiplier, and the hand shows its total multiplier next to the bet.
The fee
The fee is 20% of the bet, 2 credits for every 10, taken when you deal. It’s never returned, whatever happens to the hand. The result line already counts it: “You won 48!” after a ×5 win on a 10 bet means 60 back minus the 12 you spent.
Strategy
Double more when a spark card is already in your hand. A multiplier only works on wins, and doubling doubles the win it multiplies. The Hint button counts the spark cards you’re holding (not the ones you might still draw), and it changes its advice a lot:
- A hard 12 against a dealer 4, 5 or 6 normally stands. With any spark card in it, even ×2, the hint doubles.
- A soft 18 (ace-7) against a 2, 7 or 8 normally stands. With a spark card, the hint doubles.
- With ×5 or more, the hint doubles hands as weak as a hard 13 against a dealer 2 to 6.
Without a spark card, play classic blackjack. The rules are the classic six-deck game, and so is the hint’s advice.
Don’t chase the sparks. You can’t choose which cards come. The fee is paid on every hand, and most rounds end without a spark card in a winning hand: in our measurement about 1 round in 30 paid a multiplied win.
The odds
Over sixteen million hands played with the hint’s strategy, the house edge came out at about 0.86% of the bet, give or take 0.19%. Counting the fee as part of what you spend, that’s about 0.72% of the 12 credits a 10 bet costs. Most of the time you pay the fee and play ordinary blackjack; the return comes in rare large wins.
For blackjack without the fee and the sparks, play classic Blackjack. Progressive 21 has a jackpot side bet, and Raise 21 lets you double your bet after seeing the dealer’s card.
If you enjoy Spark 21, try Speed Baccarat or Split Gems next.
