Welcome to our deep dive on Occultum 81 — the demo, the maths, and whether it earns a spot in your rotation. Built by Apollo Games, it lands as a release with medium low volatility and a return-to-player rate of 99%. It first went live in 2018 and still earns its place today. If everything lines up, Occultum 81 can pay up to 5,000x your bet. It's given an engaging visual treatment and plays out on 5 reels and 15 paylines. So does it deliver? Let's get into it.
Written by Daniel Chen · Last updated: January 2026
This game, Occultum 81, is the work of Apollo Games. Presentation-wise it's given an engaging visual treatment, and it leans toward medium low variance at a published RTP of 99%. Under the hood you'll find 15 paylines across 5 reels.
Where Occultum 81 earns its keep is the feature set. Look out for scatter symbols that unlock free spins and extra bonus rounds. The medium low volatility makes it forgiving on the bankroll, ideal for relaxed, longer sessions. All told, it's a solid entry in the Apollo Games catalogue.
At 99%, this slot offers an excellent return to player rate, well above the industry average of ~96%. This makes it one of the more generous slots available in terms of long-term payout potential.
Medium-low volatility offers a good balance of regular wins with occasional larger payouts. Expect frequent hits with modest amounts, suitable for casual players who want low-risk entertainment.
About 1 in 3 spins results in a win. This is a moderate hit frequency that balances win frequency with payout size.
Occultum 81 features scatter symbols that can trigger free spins rounds. Landing the required number of scatter symbols anywhere on the reels activates the free spins feature, giving you extra chances to win without additional bets. During free spins, special modifiers may apply to boost your winning potential.
3.0 / 5 — Good
Occultum 81 by Apollo Games is a solid offering that delivers good entertainment value. The 99% RTP combined with medium low volatility creates a well-balanced gaming experience.