Secret Sauna

Secret Sauna is Slotmill's new 7x7 Cluster Pay Avalanche slot, launching 1 December 2026 with an RTP of up to 96.04%, High volatility and a maximum win of 10,000x your bet. It's Christmas, the snow is piling up outside, and two brothers are sticking to their most sacred family tradition: the Christmas sauna, where festive Wilds, glowing Hotspots and climbing Multipliers heat things up fast.

Match identical symbols in a cluster to create a win. Winning symbols are removed, making room for new symbols to drop and keeping the Avalanche going. Every Wild that is part of a win leaves a Hotspot behind, and when the last Avalanche of the spin is over, all Hotspots turn into Wilds, giving you one more shot at warming things up. Free Spins symbols are collected in a meter outside the reels and are removed from the grid the same way, triggering an Avalanche along the way.

In the Bonus, every Wild that is part of a win leaves a Hotspot that stays on the reels until the round ends. Wilds landing on a Hotspot add a Multiplier to it, climbing from x2 to x3, x4 and beyond. At the end of the Free Spins, all Hotspots turn into Wilds and pass their Multiplier along to that Wild. Multipliers are multiplicative, so a x2 Wild and a x3 Wild in the same winning cluster multiply that cluster's win by x6. The Super Bonus plays the same way, but with at least 2 guaranteed Wilds on every spin.

Secret Sauna also includes Slotmill's Burst Mode, Fast Track and Xtra-Bet features, letting players speed up play, jump straight to the bonus, or boost their stake for a better shot at triggering it.