Mystery Symbols Mystery Symbols
Special symbols that fall as unidentifiable shapes, then all flip at once into the same symbol after the reels stop. The more that land, the more one type of symbol expands.
| English | Mystery Symbols |
|---|---|
| Classification | Game Features |
| Also called | Mystery Symbols, Mystery Stacks, Mystery Reveal |
| Basic principle | Several symbols are revealed as the same symbol at once |
| Variations | Copy type, stack type, special symbol reveal type, sticky and growing type |
| Signature series | Mystery Reels (Red Tiger, since 2017) |
| How the result is decided | Set in advance in the spin result (RNG) |
Overview
Mystery Symbols are special symbols that look unidentifiable, like question marks or boxes, while they fall. After the reels stop, they all flip at once and turn into the same symbol. Even when several Mystery Symbols land on one spin, they usually all become the same symbol, so the more that appear on screen, the more one type of symbol expands.
Which symbol they turn into is already decided in the result of that spin, and the flip animation is just the way the result is shown. Slot symbol types and Bonus features overview cover this briefly, and this article looks at it in more detail, focusing on game-specific variations.

Mystery Symbol Variations
Copy type
In Red Tiger‘s Mystery Reels, a number appears on the Mystery Symbol, and it copies itself that many times, spreading up, down, left, and right. Once the copying is done, they all flip at the same time into the same regular symbol or trigger a wheel bonus. The same approach carried over to Mystery Reels Megaways and Mystery Reels Power Reels, and in the Power Reels version the Mystery Symbol grows to 2×2 in size.
Stack type
Here the Mystery Symbols drop as a stack that covers an entire reel. Yggdrasil’s Temple Stacks is described as having Mystery stacks that reveal 3 to 9 of the same symbol.
Special symbol reveal type
In this type, the symbols can turn into scatters or multiplier wilds as well as regular symbols. Pragmatic Play’s Mystery of the Orient is described as producing scatters and multiplier wilds from Mystery Symbols, which helps retrigger free spins.
Sticky and growing type
In this type, Mystery Symbols stay in place during the bonus and gradually get stronger. Spellbinding Mystery is a cluster-style game where Mystery Symbols landed during free spins become sticky, and the multiplier goes up by 1x for each spin they take part in.
How It Feels and the Odds
| Situation | Result |
|---|---|
| 1-2 Mystery Symbols | If the new symbol doesn’t connect with other reels, there are almost no wins. |
| Spread widely across several reels | One symbol fills several reels, so paylines or ways connect all at once. |
| Revealed as a high-paying symbol | Even with the same number of positions, the win is several times bigger than with a low-paying symbol. |
What a Mystery Symbol turns into follows the probability table in the game’s math model. So the chance of a high-paying symbol is usually lower than a low-paying one, and you can’t predict the next result by watching the reveal animation. Every result is determined by the RNG.
Mystery Symbol Games on AI Slot
| Games | Providers | Release | RTP | Max win |
|---|---|---|---|---|
| Mystery Reels | Red Tiger | 2017.06 | 96.24% | 4,991x |
| Mystery Reels Megaways | Red Tiger | 2019.03 | 98.06% | 10,346x |
| Mystery Reels Power Reels | Red Tiger | 2019.10 | 95.67% | 5,250x |
| Temple Stacks | Yggdrasil | 2020.01 | 96.1% | 25,000x |
| Mystery of the Orient | Pragmatic Play | 2023.02 | 96% | 8,035x |
| Spellbinding Mystery | Pragmatic Play | 2023.06 | 96.04% | 10,000x |
RTP and max win are based on the AI Slot game info. Not every game with “Mystery” in its name uses Mystery Symbols, so it’s a good idea to check the features in the game info.


