Heart of Tiki Slot by BGaming

Free spins start with a single 1x1 Wild locked to the reels. It never disappears - instead it drifts to a new random position each spin, a permanent fixture that keeps paying wherever it lands. Collect 3 scatters during the round and that Wild grows to 2x2. Another 3 scatters, 3x3. Then 4x4, then the full 5x5 grid. Each growth stage adds 1 to 3 extra spins and the size upgrade is irreversible. Once you hit 3x3, every remaining spin has a 9-position Wild roaming the board. Reach the 5x5 cap and the Wild fills every cell on every spin for the rest of the session - 50 paylines, all covered, nothing left to chance.

Triggering with 4 or 5 scatters gives you a head start. Four scatters at trigger means 1 scatter already pre-collected toward the first upgrade, so you only need 2 more instead of 3. Five scatters means 2 pre-collected. That difference matters more than it sounds - one fewer scatter between you and a 2x2 Wild compresses the growth timeline and stretches the high-value spins across more of the round. Carved wooden tiki masks in red, purple, blue, and green make up the premium pays, a volcano Wild erupting with orange fire against the lush green backdrop, and a golden sun-face totem as the scatter. The color separation between symbols is clean, each mask distinct enough that you never confuse one for another mid-spin.

Outside free spins, the base game runs its own version of the Wild sizing. Every Wild that lands in a regular spin has a randomly assigned size - 1x1, 2x2, 3x3, 4x4, or the full 5x5 block. Multiple Wilds of different sizes land on the same spin. Two Wilds at 3x3 and 2x2 together means 13 positions substituting at once. The Chance x2 toggle doubles scatter trigger probability at a cost of 0.5x extra per spin (so 1.5x total), and the 100x buy option drops you straight into the bonus. BGaming used a similar Polynesian shell for Tiki Elements, but the underlying math there runs on cluster pays and cell multipliers - a completely different engine despite sharing the carved-mask aesthetic.