Game Information
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Provider
ThunderSpin
Type
Slots
Reels
5
Min Bet
0.01
Max Bet
Yes
Max Win per Spin
12000
Calipso Slot: Comprehensive Data Analysis
Core Game Specifications
| Attribute | Value |
|---|---|
| Developer | ThunderSpin |
| Release Date | 2017-04-03 |
| Theme | Underwater, Mythical mermaid, Ancient Greek myth |
| Layout | 5×3 reels, 21 fixed paylines |
| Paylines | 21 |
| Bet Range | 0.21–210 per spin |
| Core Mechanics | Wild symbol substitutes for all except scatters, Sunken Treasure pick bonus with multipliers up to 5×, Free spins triggered by stacked mermaid scatter, Pearl collection during free spins increases multiplier up to 8× |
| Developer | ThunderSpin |
| Platform compatibility | PC and mobile |
Mathematical & Payout Model
Return to Player (RTP)
95.8%
Volatility
Low
Max Win Potential
1000x
Symbols & Paytable Hierarchy
| Tier | Symbol(s) | Function & Value |
|---|---|---|
| Low Tier | J, Q, K, A | Provides small, frequent wins to maintain gameplay. |
| Mid Tier | Shell, Starfish, Clam | Thematic items offering moderate payouts. |
| High Tier | Seahorse | Highest paying symbols. Top hits available with full combinations. |
| Wild | Fish | Acts as a substitute / feature trigger per game rules. |
| Scatter | Casket, Mermaid | Triggers free spins / bonus round when enough appear. |
Calipso Bonus Features Mechanics
| Feature | Trigger | Initial Award | Core Mechanic | Enhancement/Retrigger |
|---|---|---|---|---|
| Sunken Treasure Bonus | Three or more casket scatters | Pick artefacts to reveal multipliers up to 5× | ||
| Free Spins with Pearl Multiplier | Stacked mermaid scatter | 15 free spins | Collect pearl fish symbols to gain extra spins and pearls | Multiplier increases to 4× at 5 pearls, 6× at 10 pearls, 8× at 15 pearls |
Frequently Asked Questions (FAQ)
| What is the RTP of Calipso? | The RTP is 95.8%. |
| What is the volatility of Calipso? | The game has low volatility. |
| What is the maximum win multiplier? | The maximum win is 1000× the stake. |
| How do I trigger the Sunken Treasure bonus? | Land three or more casket scatter symbols anywhere to trigger the pick bonus. |
| How do I trigger free spins? | Land the stacked mermaid scatter to receive 15 free spins. |
| How do multipliers increase during free spins? | Collect pearls via pearl fish symbols; multiplier increases to 4× at 5 pearls, 6× at 10 pearls, and 8× at 15 pearls. |
| What does the wild symbol do? | The fish wild substitutes for all symbols except scatters. |
Calipso Performance Summary: Strengths vs. Weaknesses
Strengths
- Engaging underwater theme with mythological elements
- Multiple bonus features including pick game and free spins
- Low volatility suits extended play sessions
Weaknesses
- Below‑average RTP
- Fixed paylines limit betting flexibility
Overview
Calipso is an underwater‑themed slot by ThunderSpin featuring 5 reels and 21 fixed paylines. It offers low volatility gameplay with bonus features including wilds, scatters, a Sunken Treasure pick bonus, and a free spins round with increasing multipliers.
Rachel Pine is our slots expert who has worked in the online gambling industry for 10+ years. Over the course of her career, Rachel has reviewed more than 30,000 slots.
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