18+ For entertainment only No real money play No prizes of monetary value No in-app purchases
before the dome opens
Every instrument here is free and runs on stardust. Stardust cannot be bought, sold or exchanged, and there are no prizes of monetary value.
Your answer is remembered in this browser so we only ask once.
The games here are for adults only. If gambling or gaming is worrying you or someone close to you, GamCare's free, confidential helpline is open day and night on 0808 8020 133.
close the shutters
Choose how long the instruments stay covered on this device. You can still read every page.
A break cannot be shortened once it starts. For a break from every gambling site in Great Britain, GAMSTOP is free.
a note from the hall
In that time you have played 0 rounds, and your stardust has moved by 0. Stardust is only points, but time is real.
A note on storage
Orrery Hall sets no cookies and runs no trackers or adverts. Your age answer and this choice are kept in this browser. Accept, and your stardust and Logbook stay on this device; choose Session only, and they are forgotten when you close the tab. How storage works
10stake
Choose a stake to begin.
A single deck and one question: will the next card be higher or lower? Each right call raises the multiplier by the true odds. Collect whenever you like, or keep climbing up to ten steps.
The calm one. You can see the odds, you choose the risk, and you decide when to stop.
It is a good place to practise stopping on purpose: pick a step before the round and collect there.
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.
Each right call multiplies what is riding by the true odds of that call. If 8 of the 12 possible ranks are higher, a right "higher" call multiplies by 12 ÷ 8 = 1.5. The round starts at × 0.97, so the return is 97 per cent however you play.
| Chance of the call | Multiplier for a right call |
|---|---|
| 90% | × 1.11 |
| 75% | × 1.33 |
| 60% | × 1.67 |
| 50% | × 2 |
| 40% | × 2.5 |
| 25% | × 4 |
| 10% | × 10 |
