If you’ve spent any time around coin-collect slots, you know the format: fill a grid, collect multipliers, chase a jackpot. Evoplay’s Queen of Sirens does not reinvent that format, but it adds enough wrinkles — a Sticky Coin that vanishes if you change your bet, an Octopus that duplicates every value it can reach, and a multiplier mechanic that stacks in a way most reviews get wrong — to make it worth understanding properly before you play.
This review covers everything you need to know: confirmed stats from the developer, a step-by-step breakdown of each feature, a clear explanation of the jackpot conditions, and an honest take on who this game actually suits.
Quick Stats
| Parameter | Value |
|---|---|
| Developer | Evoplay |
| Release | June 2025 |
| Grid | 3×3 (9 positions) |
| Paylines | None |
| RTP | 95.97% |
| Volatility | High |
| Min bet | $1 |
| Max bet | $100 |
| Max win | 323,475 (in stake currency) |
| Jackpots | 4 fixed tiers |
| Bonus Buy | Yes |
| Mobile | Android, iOS, desktop |
One note on RTP: the official Evoplay page lists 95.97%, but several aggregators display 96.05%. The difference likely reflects a higher-configured variant at certain operators. 95.97% is the base figure.
Theme and Visual Design
Queen of Sirens is set underwater — ancient stone pillars, coral reefs, and the kind of deep-sea blue that’s become standard in the genre. A mermaid with an azure tail and gold seashell is the central character; she appears during the Luck of Aurora feature and gives the game most of its visual identity.
The grid sits in the middle of the screen with controls underneath. It’s a clean layout. Evoplay hasn’t cluttered the interface, which matters when you’re watching symbols accumulate across a 3×3 grid and trying to track values.
The visual style puts Queen of Sirens in the same category as Sea of Wealth, Ocean Catch, and Evoplay’s own Gold of Sirens — undersea mythology is a crowded lane. What differentiates this one mechanically rather than visually is the combination of Sticky Coins, the Octopus collector, and the stacking Aurora multipliers.
How the Base Game Works
The game runs on a 3×3 grid — nine positions, no paylines. There are no winning combinations in the traditional sense. In the main game, your job is to land qualifying symbols and set up for a bonus round. Regular spins pay nothing on their own; the money is entirely in the bonus mechanics.
The central line of the grid is what matters for triggering. Land enough qualifying symbols — including the Octopus — on that central row, and you activate the Bonus Game. The exact threshold isn’t spelled out in public documentation, but the Octopus acts as a primary activator alongside the Bonus Coin symbols already on the reels.
If you’re coming from a traditional payline slot, the base game will feel slow. That’s by design. The main game exists to build a setup — Sticky Coins locking in, Bonus Coins accumulating values — for the bonus round where the actual payouts happen.
One thing worth being clear about for players new to the coin-collect format: the grid is 3×3, not the 5×3 or 6×5 layouts you see on video slots. Nine positions total. This smaller canvas means the full-grid condition (nine symbols) is mathematically reachable within a single bonus round, but only if the spin-reset mechanic keeps feeding new symbols before your count hits zero. On a larger grid, full fills would be nearly impossible — on a 3×3, they happen, just not often under high volatility.
The absence of paylines also means there’s no base-game scatter logic, no win-both-ways mechanic, and no regular spin payout structure to fall back on. Every spin in the main game is either building toward a trigger or producing nothing. Players who like steady low-level returns from regular spins should look elsewhere.
Symbol Breakdown
Bonus Coin
The Bonus Coin appears across all three game modes: main game, Bonus Game, and Ultra Bonus Game. Each one holds a random value of ×1, ×2, ×3, or ×4 the bet. The catch: Bonus Coins do not pay during regular spins. Their values are only collected and paid out when the Bonus or Ultra Bonus Game is running. So in the main game, they function as setup pieces — building up the board — and their contributions cash out only when the bonus round starts.
Sticky Coin
The Sticky Coin shows up in the main game only and stays on the reels once it lands. It holds a random value of ×5, ×6, ×7, ×8, or ×9 the bet — higher than a standard Bonus Coin. When a Bonus or Ultra Bonus Game triggers, the Sticky Coin carries that stored value into the round.
The critical detail most reviews skip: if you change your bet after a Sticky Coin has landed, the symbol is removed from the reels. Gone. So if you land a ×9 Sticky Coin and then reduce your stake, you lose it before the bonus triggers. This is not a minor footnote — it’s a real decision point for players who adjust bets mid-session.
Mystic Symbol
There are two variants of the Mystic Symbol, and most review sites conflate them.
The standard Mystic Symbol transforms into any other symbol (except the Sticky Coin) after a Bonus or Ultra Bonus Game ends. Its transformation is random within that range.
The Mystic Jackpot Symbol is a separate symbol with a guaranteed jackpot assignment: when it lands, it contains either the Mini (×10), Minor (×20), or Major (×50) jackpot. It cannot award the Grand Jackpot — that requires a different condition entirely (covered below).
Octopus
The Octopus holds no standalone coin value. In the main game, it acts as one of the activators for the Bonus Game — it needs to land on the central line to contribute to the trigger.
During the Bonus or Ultra Bonus Game, the Octopus behaves differently. When it lands, it gathers all the values and jackpots from every Bonus symbol that has previously appeared during that round and duplicates those rewards across the reels. This is the mechanic that creates the large win scenarios — an Octopus landing late in a well-loaded bonus round can multiply the accumulated value across the whole board. Most articles describe it as “collecting values,” which is accurate but undersells the duplication effect.
The Bonus Game: How It Actually Works
The Bonus Game triggers when qualifying symbols — including the Octopus — land on the central line of the grid. All symbols that contributed to the trigger stay in their positions; they don’t disappear after activation.
Once triggered, the round starts with 3 spins. Each time a new Bonus symbol lands on the reels, the spin count resets to 3. This is the core tension of the format: every new symbol extends the round, and a populated grid takes more spins to fill because there are fewer open positions — but each symbol that lands refreshes your remaining spins.
The round ends in one of two ways:
- The spins run down to zero without filling all nine positions.
- All nine grid positions are filled with Bonus symbols — the full-grid win condition.
Only the second outcome unlocks the Grand Jackpot (500× the bet). A partial fill still pays out the accumulated coin values and any jackpots from Mystic Jackpot symbols, but the Grand requires the complete board. Given that this is a high-volatility game with a 3-spin reset mechanic on a 9-position grid, full fills are not common. That’s not a criticism — it’s just the correct framing for what the Grand Jackpot is: a rare maximum-outcome event, not a regular bonus-round payout.
One detail that affects how you read a bonus round in progress: the symbols that triggered the round stay locked in place, so the grid is never truly empty when spins begin. If you triggered with three symbols on the central line, you start the Bonus Game with three of nine positions already filled. That’s a meaningful head start — you need six more positions to fill, not nine. A strong trigger position (central row plus any other Bonus Coins that landed earlier) reduces the distance to a full-grid outcome, though the randomness of where new symbols land on subsequent spins still determines the final count.
The Ultra Bonus Game: The Random Shortcut
The Ultra Bonus Game can trigger randomly at any point during a main game spin — no special landing condition required. The difference from the standard Bonus Game is structural: before your spins begin, the game automatically pre-places 3 or more random symbols on the central line of the grid.
That pre-placement is significant. In a standard Bonus Game, you start with a mostly empty board and 3 spins to build it. In the Ultra Bonus, you start with at least 3 symbols already in place on the central row, which immediately changes the coverage and gives the round a better foundation.
Additionally, the Luck of Aurora feature is always activated at the start of the Ultra Bonus Game — and it fires more frequently throughout the round than it does in the regular Bonus Game. In practical terms, the Ultra Bonus gives you more multiplier coverage by default, which is why players tend to get larger payouts from it when it hits.
You cannot manually trigger the Ultra Bonus through regular play — but you can buy into it directly via the Bonus Buy feature.
Luck of Aurora: The Multiplier Mechanic
Luck of Aurora is where this game separates from most coin-collect slots, and it’s also the mechanic most often described inaccurately.
When activated, the mermaid fires between 1 and 9 water splashes onto random cells. Each splash leaves a ×2 multiplier on that cell. That part most reviews get right.
What they get wrong: if a subsequent Aurora activation (or a second activation within the same round) hits a cell that already has a ×2 multiplier, the multiplier doesn’t become ×4. It increases by +1 — so one hit gives ×2, a second hit on the same cell gives ×3, a third hit gives ×4, and so on. The stacking is additive, not multiplicative. This distinction matters for win estimation: a cell hit three times by Aurora is worth ×4 the base coin value on that position, not ×8.
In the Ultra Bonus Game, where Aurora fires more often, cells can accumulate significant multipliers if splashes keep landing on the same positions. The upper end of those stacks — combined with an Octopus duplication — is where the game’s maximum win potential lives.
For context on what that looks like in practice: a cell with a ×5 Sticky Coin value and three Aurora hits would carry a ×4 multiplier on a ×5 coin — a return of 20× the bet from a single position. The Octopus then duplicates that value across the reels. The combination of a well-loaded Sticky Coin, repeated Aurora hits on the same cell, and an Octopus landing late in the round is the sequence that produces the headline numbers. It requires multiple favorable events in the correct order, which is precisely why the game’s volatility is classified as high.
Aurora can activate multiple times within a single bonus round. In the standard Bonus Game, it fires randomly. In the Ultra Bonus, it’s guaranteed at the start and more likely to refire throughout. Players who have watched their bonus round produce a moderate return on the first Aurora activation should keep their expectations level — subsequent activations may or may not hit the same cells, and the splash distribution is random each time.
Mystic Chest
The Mystic Chest unlocks hidden rewards during the bonus rounds. Evoplay’s official material doesn’t break down the specific reward range — it’s described as “hidden secrets.” Based on the game’s structure, the Chest is a secondary prize element within the bonus rounds rather than a standalone high-value feature.
Jackpot Structure
Queen of Sirens has four fixed jackpots. Fixed means they don’t grow over time — each tier pays a set multiple of your bet at the moment of winning, regardless of when you play or how large the prize pool is at any casino.
| Jackpot | Payout |
|---|---|
| Mini | 10× the bet |
| Minor | 20× the bet |
| Major | 50× the bet |
| Grand | 500× the bet |
How the Mini, Minor, and Major jackpots are won: The Mystic Jackpot symbol lands during a Bonus or Ultra Bonus Game with a guaranteed assignment to one of these three tiers. You don’t select which tier — the game assigns it randomly. The symbol guarantees a jackpot, but not which one.
How the Grand Jackpot is won: This is separate from the Mystic Jackpot symbol entirely. The Grand requires every one of the nine grid positions to be filled with Bonus symbols during the Bonus Game. A full-grid fill during a Bonus round automatically awards 500× the bet as the Grand Jackpot. This is independent of Aurora multipliers — the 500× is a flat payout for completing the board. Aurora-boosted coin values on a full grid would add to the total on top of that.
At $100 max bet, the Grand Jackpot pays $50,000. The overall max win of 323,475 represents the theoretical ceiling across coin values, multipliers, jackpots, and Octopus duplication combined.
One note: Evoplay classifies this game as a jackpot slot, and it is — but fixed jackpots work very differently from progressive ones. If you’re used to network progressives (where a pool builds over time), the Grand at 500× the bet may feel modest. At a $1 minimum bet, that’s $500. The scale of the jackpot is directly tied to your stake, which is standard for fixed-jackpot mechanics.
Bonus Buy
The Bonus Buy feature lets you skip the main game and purchase direct entry into either the Bonus Game or the Ultra Bonus Game. Both bonus modes are available as separate buy options.
This is useful for players who find the main game buildup tedious and want to spend their session in the rounds that actually pay. It also makes jackpot hunting more efficient — since jackpots are only available during the bonus rounds, Bonus Buy concentrates your play where jackpot exposure actually exists.
The cost of the Bonus Buy is not published in Evoplay’s official material and varies by operator configuration. Do not assume a specific multiple — check the game directly at your casino.
One strategic note: if you’ve been playing the main game and a Sticky Coin has landed, buying into the bonus round through Bonus Buy may or may not carry the Sticky Coin’s value — the rules around this are not publicly documented. If Sticky Coin preservation in Bonus Buy is important to your session, test it in demo mode before committing.
Max Win and Realistic Session Expectations
The maximum win is 323,475 in stake currency. At a $100 bet, that’s $32,347,500 — but the 323,475 figure is a theoretical ceiling, not a typical outcome.
More practically: this is a high-volatility game with no payline wins in the base game, a bonus round that requires accumulating symbols across 9 positions on a 3-spin reset, and multipliers that depend on Aurora hitting occupied cells multiple times. Sessions can run cold for an extended period — the base game produces no payouts between bonus triggers, and bonus triggers don’t always generate substantial returns.
The game is built for players who are comfortable with long dry stretches in exchange for the occasional large bonus outcome. At a $1 minimum bet, the exposure is manageable. At $100, the variance will be felt significantly over a short session.
No free spins exist in this game. Players expecting free-spin multiplier trails will find the coin-collect format different in pacing — it’s more stop-start, with the bonus round determining whether a session was worthwhile.
Who Should Play Queen of Sirens
High-volatility slot players who specifically enjoy coin-collect mechanics and are comfortable with sessions that produce nothing outside bonus rounds. If you’ve played titles like Money Train, Cash Bonanza, or any Evoplay coin-collect release, the format is familiar.
Bonus hunters using Bonus Buy. The Bonus Buy option concentrates your play into the rounds that matter and skips the slower main game phase. This suits players with a set session budget who want to maximize their time in bonus-eligible play.
Casino streamers and max-bet players. The $1–$100 bet range and the visual spectacle of Luck of Aurora on a full board are a natural fit for content. Full-grid outcomes with stacked Aurora multipliers and an Octopus duplication in the same round produce the kind of large hit numbers that make for watchable content.
Players who track Sticky Coin builds. If you enjoy the setup phase — watching a Sticky Coin lock in and protecting it by keeping your bet steady — the main game has a strategic layer that reward-focused players tend to engage with. It’s light strategy, but it’s there.
This game is probably not right for you if:
You prefer high-frequency, small-win slots. Queen of Sirens will go long stretches without a meaningful payout in the base game. It’s also not the right pick if you want free spins — there are none. And if you’re used to jackpots that grow over time (network progressives), the fixed-jackpot structure here, where the Grand pays 500× your current bet rather than a pooled prize, is a fundamentally different product.
Verdict
Queen of Sirens is a competent coin-collect jackpot slot with a few mechanics that are better than most reviews give credit for. The Sticky Coin’s bet-change vulnerability adds a real decision point that most similar games don’t have. The Luck of Aurora stacking mechanic — additive, not multiplicative — is more nuanced than the ×2-per-splash description suggests. And the Octopus as a value duplicator rather than just a collector gives the bonus rounds a higher ceiling than the symbol breakdown implies on paper.
The underwater/mermaid theme is well-executed but not unique — Evoplay’s own Gold of Sirens covered similar ground, and the genre is crowded. If visual novelty matters to you, this won’t stand out. If you’re evaluating it on mechanics, the combination of a well-designed bonus trigger, meaningful Sticky Coin decisions, and the Luck of Aurora stacking places it solidly in the upper tier of the coin-collect format.
RTP of 95.97% is slightly below average for the category but not dramatically so. The fixed jackpot structure is transparent — no hidden mechanics, no pool dependency. The Grand at 500× the bet is achievable through a defined condition (full 9-position fill), not random chance against a progressive pool.
For high-volatility coin-collect players, it’s worth the session. Go in with a clear budget, keep your bet steady if a Sticky Coin lands, and understand that the bonus round is where the game lives — not the spins between them.
Pros and Cons
Pros:
- Clearly defined jackpot conditions — no ambiguity about how each tier is won
- Sticky Coin adds a base-game decision layer most coin-collect slots skip
- Luck of Aurora stacking mechanic creates genuine multiplier depth
- Octopus duplication expands bonus round ceiling meaningfully
- Bonus Buy available for both Bonus and Ultra Bonus Game
- Cross-platform: Android, iOS, and desktop
Cons:
- Base game produces zero payouts between bonus triggers — long dry patches are standard
- No free spins; players expecting that format will need to adjust expectations
- Grand Jackpot (500× bet) requires a full 9-position grid fill — rare at high volatility
- RTP of 95.97% sits slightly below average
- Bonus Buy cost is not publicly disclosed — requires checking at each casino
- Theme is crowded; nothing visually distinguishes this from comparable undersea titles
FAQ
What is the RTP of Queen of Sirens? The official Evoplay figure is 95.97%. Some casino operators may configure a variant version that displays as 96.05% on aggregator sites. Always check the paytable in-game at your casino for the configured RTP.
Does Queen of Sirens have free spins? No. The game uses coin-collect bonus mechanics — the Bonus Game and Ultra Bonus Game — rather than free spins. There is no free spins round.
How do you trigger the Bonus Game? By landing qualifying symbols, including the Octopus, on the central line of the 3×3 grid during the main game.
What is the Grand Jackpot and how do you win it? The Grand Jackpot pays 500× the bet and is awarded only when all nine positions on the grid are filled with Bonus symbols during the Bonus Game. It cannot be won through the Mystic Jackpot symbol.
What does Luck of Aurora do? It fires 1–9 water splashes onto random grid cells during the Bonus or Ultra Bonus Game. Each splash places a ×2 multiplier on that cell. If a cell is hit again, its multiplier increases by +1 (not doubled again) — so two hits give ×3, three hits give ×4, and so on.
What is the maximum win in Queen of Sirens? 323,475 in stake currency. This is the theoretical ceiling combining coin values, stacked Aurora multipliers, and jackpot payouts.
Can I play Queen of Sirens on mobile? Yes. The game runs on Android, iOS, and desktop browsers.
What is the minimum bet? $1 per spin.
Does the Sticky Coin disappear if I change my bet? Yes. If a Sticky Coin has landed on the reels during the main game and you adjust your bet before a bonus round triggers, the Sticky Coin is removed from the reels.
Is there a Bonus Buy option? Yes. Players can purchase direct access to either the Bonus Game or the Ultra Bonus Game. The specific cost multiplier is not published in official documentation and varies by operator.
