Calipso

Thunderspin's Calipso is a video slot featuring 5 reels and 3 rows, with 21 fixed paylines set in an enchanting underwater realm filled with treasures, sea creatures, and mermaids. The game draws inspiration from oceanic mythology, showcasing symbols such as seahorses, oysters with pearls, starfish, mollusks, and the mermaid Calipso herself. A Wild symbol, represented by a fish, can replace regular symbols to assist in creating winning combinations. There are two types of Scatter symbols in the game; one is a decorative treasure chest that activates the Sunken Treasure Bonus Game when enough appear, while the other is the mermaid Calipso, which acts as a stacked reel scatter to unlock the Free Spins feature. During the Free Spins round, players encounter a special scatter symbol, a fish that carries pearls, which grants additional free spins and helps accumulate "pearls" to enhance multipliers. Collecting 5, 10, or 15 pearls during this round boosts the win multiplier to 4×, 6×, or 8×, respectively. The Sunken Treasure Bonus Game allows players to select from various underwater compartments to uncover cash prizes and multipliers, continuing until an empty compartment is chosen. Bets can be adjusted from low to high, catering to a variety of player preferences, and Calipso does not include a Bonus Buy feature.

You can play it for real money.