2. Campaign period: 23 October 2026, 00:00 UTC – 1 November 2026, 23:59 UTC.

3. Participating games: all VoltEnt games.

4. The campaign is available only in real-money mode. To take part, simply place a qualifying bet in any participating game during the campaign period — no registration and no additional cost.

5. There is no minimum bet: all bets in participating games qualify.

6. Any qualifying bet can trigger a Mystery Box with a random cash prize. One bet can win only one prize, but a player can win more than one prize during the campaign. Prizes are awarded randomly throughout the campaign period.

7. Prize pool: up to €1,750,000 in cash prizes, divided into 7,000 Mystery Boxes. Each Mystery Box contains one of the following prizes:

• €250
• €50
• €20
• €10
• €5

8. The Mystery Booster campaign is part of a VoltEnt promotional campaign with a total maximum prize value of €6,000,000.

9. Prizes are determined by the RNG, so the full prize pool may not be paid out during the campaign period.

10. The number of available prizes is updated instantly.

11. Depending on the casino configuration, prizes are credited to the player's account instantly upon receiving the winning notification or after a period of time. Prizes are paid out as per the prize pool tab.

12. Cash prizes have no wagering requirements. Prizes won while playing with bonus funds are paid out in bonus funds.

13. Cash prizes are paid in the currency of the winning bet, converted from EUR at the exchange rate at the time the winning bet was placed.

14. Only players of legal age as defined by their jurisdiction and with verified casino accounts are eligible to win prizes. Any violation of King Billy's general Terms and Conditions may result in disqualification.

15. King Billy and VoltEnt reserves the right not to pay out a cash prize where the win results from any obvious error, mistake or technical fault (including incorrect game payouts), whether caused by a machine or human error, or from cheating or collusion with other players.

16. King Billy and VoltEnt reserves the right to modify, discontinue or terminate this promotion at any time for any reason and to change its terms. Previous terms will be honoured for players who claimed prizes before the change.

17. In case of any discrepancy between a translated version and the English version of these terms, the English version prevails.

18. King Billy's general promotional Terms and Conditions apply.