Blackjack · 20 rounds · Sep 25, 2026, 8:38 PM UTC
Round 20
Dealer
Round 20 result · Dealer 17
Claude Opus 5.5
Hand 1 · 18 · bet 10
Win +10
Basic strategy for 6 decks with the dealer standing on soft 17 says to double soft 18 (A-7) against a 3. The dealer's weak upcard makes the extra bet worth more than standing.
Basic strategy says to stand on hard 13 against a dealer 5, because the dealer's bust chance is high.
A hard 20 against a dealer 10 is a strong favorite, so standing is correct basic strategy. Splitting tens would give up that edge.
A pair of aces should always be split per basic strategy, including against a dealer 9, since each ace becomes a strong starting card.
Basic strategy for a 6-deck game with double after split says to split 7s against a dealer 7. Each 7 is a better starting hand than a hard 14 against a dealer's likely 17.
Hard 11 against a dealer 7 is a standard double. Double after split is allowed here.
Hard 12 against a dealer 7 is a hit in basic strategy, because a dealer 7 is strong and standing on 12 loses too often.
Basic strategy is to stand on a hard 17 against any dealer upcard, including a 7.
Basic strategy says always split a pair of 8s. A hard 16 against a dealer 8 is a poor hand, while two hands starting from 8 do better, especially with double after split allowed.
A pair of 8s against a dealer 8 should be split under basic strategy, and resplitting is allowed up to 4 hands. Playing 16 as a single hand against an 8 is much worse.
Hard 18 against a dealer 8 is a clear stand under basic strategy. Hitting or doubling would risk busting a hand that already rates as a favorite.
Hard 10 against a dealer 8 is a standard double under basic strategy, and double after split is allowed.
Basic strategy for a hard 13 against a dealer 8 is to hit, because the 8 is a strong upcard and standing on 13 loses more often.
Basic strategy says to hit a hard 16 against a dealer 8, since standing loses more often than risking the bust. The dealer's 8 is likely to make 17 or more.
Basic strategy says to hit hard 15 against a dealer 7, since standing loses more often than risking a bust.
A hard 18 against a dealer 7 is a stand in basic strategy. Hitting risks busting, while standing wins or pushes against most dealer outcomes.
A hard 20 against a dealer 3 is a strong favorite, so basic strategy says stand. Splitting tens gives up a likely win for a worse expected value.
A pair of fives is played as a hard 10, and basic strategy says to double hard 10 against a dealer 5 in a 6-deck S17 game. Splitting fives would give up that strong starting total.
Under basic strategy, a hard 10 against a dealer 9 is a double. It has a better expected value than hitting.
A hard 20 against a dealer 4 is a strong made hand. Basic strategy says to stand rather than split tens.
Basic strategy says to hit soft 15 against a dealer 10. Hitting cannot bust, and doubling is only correct against a dealer 4-6.
Basic strategy says to hit soft 18 against a dealer 10. Standing on 18 loses more often than hitting, and a soft hand can't bust on one card.
Hard 18 against a dealer 10: basic strategy is to stand, because hitting risks busting on most cards.
Hard 18 against a dealer 6 is a clear stand under basic strategy. The dealer has a high bust chance, and any hit or double risks busting a strong hand.
Under basic strategy a hard 8 against a dealer 3 is a hit, since doubling 8 is not correct against a 3. Standing on 8 is clearly worse.
Hard 17 against a dealer 3 is a stand under basic strategy, since hitting risks busting far too often.
Basic strategy is to always stand on a hard 17 against a dealer 10. Hitting busts too often to be worth it.
A hard 8 against a dealer 10 is a clear hit under basic strategy. Doubling is not favorable here.
Basic strategy is to stand on a hard 18 against a dealer 10, since hitting carries a high risk of busting.
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Session result: +85 chips over 20 rounds
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