Blackjack · 20 rounds · Sep 25, 2026, 8:38 PM UTC
Round 20
Dealer
Round 20 result · Dealer 25
Claude Opus 5.5
Hand 1 · 21 · bet 10
Win +20
Hard 20 against a dealer 4 is a strong made hand, and basic strategy is to stand. Splitting tens gives up a likely win.
Hard 11 against a dealer 6 is a textbook double under basic strategy. The dealer's bust chance is high and any 10-value card gives us 21.
Hard 20 against a dealer 10 is a strong standing total. Splitting tens gives up a likely win, so basic strategy is to stand.
Basic strategy for a hard 12 against a dealer 10 is to hit, since standing loses more often against a strong upcard.
Hard 15 against a dealer 5 is a basic-strategy stand. The dealer has a high chance of busting, so I avoid risking a bust myself.
Basic strategy says to hit soft 14 against a dealer 9; doubling only pays off against dealer 5-6, and standing on 14 is weak.
Basic strategy for a hard 14 against a dealer 9 is to hit, because the dealer's strong upcard makes standing lose more often than the risk of busting.
Basic strategy says to hit a hard 13 against a dealer 8. The dealer is fairly likely to finish with 17 or more, so standing does worse than taking a card.
Basic strategy says to double a hard 9 against a dealer 3 through 6. The dealer's 5 is a weak upcard with a high bust chance.
Basic strategy says to stand on a hard 13 against a dealer 3 in a 6-deck S17 game. The dealer busts often from a weak upcard, and hitting risks busting.
Hard 19 against a dealer 10 is a clear stand in basic strategy. Hitting or doubling would risk busting a strong hand.
Basic strategy says to hit a hard 14 against a dealer 8, because the dealer's strong upcard makes standing worse than taking the bust risk.
A hard 19 against a dealer 7 is a clear stand under basic strategy. Hitting or doubling would only risk busting a strong hand.
Basic strategy for soft 13 against a dealer 6 in a 6-deck S17 game with double allowed on any first two cards is to double. The dealer's 6 is the weakest upcard.
Hard 16 against a dealer 10: surrender isn't offered, so basic strategy says hit, which loses slightly less than standing.
Hard 16 against a dealer 8 is a hit in basic strategy, since the dealer is too likely to finish 17-18 for standing to pay off, and surrender isn't available.
Basic strategy says to hit soft 17 against a dealer 10. Standing on 17 does poorly against a strong upcard, and hitting cannot bust this hand.
Hard 17 against a dealer 10: basic strategy says stand, since hitting busts too often.
Hard 15 against a dealer 10 is a hit under basic strategy when surrender is not available. Standing loses more often, because the dealer will usually make 17 or better.
A hard 19 against a dealer 10 is a stand under basic strategy. Hitting risks busting for very little gain.
Basic strategy says to hit a hard 13 against a dealer 9, because the dealer rarely busts with a 9 showing.
A hard 20 against a dealer 9 is a clear stand, since any hit very likely busts and 20 is a strong total.
Basic strategy says to double a hard 11 against a dealer 2 in a 6-deck S17 game, since doubling has the highest expected value here.
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Session result: +20 chips over 20 rounds
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