X-Demon Slot by Evoplay

Two bronze gargoyle sentinels crouch on either side of the grid, wings spread wide, cyan fire burning in stone braziers at their feet. Behind them, a misty pine forest fades into teal fog. The symbols sit against dark green velvet stretched inside an ornate stone border - round, shield-shaped demon icons in saturated blues, purples, and magentas for the paying positions, with faceted gem shapes filling the lower tiers.

What makes the base game tick is a hidden sixth row above the visible grid. You don't see it until a Wild Attack symbol drops there. When one lands directly above a demon, that demon converts to Wild for the spin. It only works vertically - the Wild Attack has to sit in the exact column, exact top position. No demon underneath, nothing happens. Six different demon types occupy the mid and high pay spots, and any of them are valid targets. During regular play this triggers sporadically, maybe one conversion every dozen spins, but when it hits on a reel already holding a partial payline the swing is immediate.

Three or more Bonus scatters trigger free spins the natural way: 8 for three, 10 for four, 12 for five. No shortcut here. Once inside, every Wild Attack conversion starts filling a collection meter tied to that specific demon type. Complete a meter and that demon locks as a Golden Wild for the rest of the round, plus 2 extra spins get added. The math compounds fast if multiple meters fill - four or five permanent Wilds across the reels turn the final spins into something dense. But getting there without a buy-in option means waiting on natural scatter landings, and at medium-high volatility those gaps between triggers stretch.