18+ For entertainment only No real money play No prizes of monetary value No in-app purchases
before the dome opens
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a note from the hall
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Dealer –
Dealer draws to 16 and stands on all 17s · Eclipse pays 3 to 2
You –
10stake
Choose a stake to begin.
Classic twenty-one against the house. Get closer to 21 than the dealer without going over. Two cards worth 21 make an eclipse, which pays 3 to 2.
The deepest instrument in the hall. Decisions matter here: standing on 12 against a dealer 6 is a very different evening from hitting it.
Our guide to twenty-one in Observations covers the handful of choices that matter most.
Long-run return is what the game gives back on average over millions of rounds, checked by simulation. Any single evening can land far above or below it.
These are the exact numbers the game uses. Every round is drawn fresh by your browser's secure random number generator, and nothing that happened before changes what happens next.
| Result | Returns |
|---|---|
| Eclipse (ace + ten-value card) | × 2.5 of the stake |
| Win | × 2 of everything staked |
| Tie | Stake returned |
| Lose or go over 21 | Nothing |
Six decks, shuffled before every hand. No splitting and no insurance, to keep each hand simple. Played well, the long-run return is about 99 per cent.
