Mystic Potion Slot by PG Soft

Four matching symbols in a 2x2 square merge into a single Big Symbol carrying a multiplier between x2 and x500. That formation rule is the core of everything. Standard cluster wins need 5 or more connected symbols touching horizontally or vertically, and after each payout the winning symbols collapse, dropping new ones in from above. But when 4 identical symbols happen to sit in a square shape during any round - before or after a cascade - they fuse, and whatever multiplier the Big Symbol draws gets collected into a running total at the bottom of the screen. Multiple Big Symbols forming across a single spin stack their multipliers together, and at the end of the spin the total win gets multiplied by the accumulated sum.

The multiplier resets after each spin in the base game. Free spins change that. Three scatters award 15 spins (each extra scatter adds 2, retriggerable), and all multipliers collected from Big Symbols persist across the entire round instead of clearing between spins. So a x15 from spin 2 and a x30 from spin 5 sit together as x45 applied to every remaining spin's total win. The accumulation is additive, not multiplicative, but across 15+ spins the stack grows fast enough to push toward the 10,000x cap. For 85x your bet, the Feature Buy skips straight into the free spin round - useful when you'd rather not wait for three scatters on a grid this size.

Warm amber tones fill the background - a wizard's workshop cluttered with spell books, candles, and glass bottles. The symbols are potion flasks in different colors: a glowing orange orb, a tall green bottle, a squat blue jar with ice crystals, a purple diamond-shaped vial. Card suit pips in pink, teal, red, and violet handle the low pays. Wilds are bundled blue berries and substitute for everything except scatters. The whole alchemist's den palette leans into deep browns and golds with purple accents, darker than most PG Soft games, and the Big Symbol animation - four bottles merging into one oversized flask with a multiplier stamped across it - is the visual payoff that ties the mechanic to the theme.