World Eaters Slot by ELK Studios

Progress saves between sessions. That alone puts this game in rare territory for slots. Five worlds unlock sequentially - Whale, Pipe, Fireworks, Tree, Volcano - each requiring three feature triggers at the same bet level before the next one opens. Start a session on Tuesday, come back Friday, and your unlocked worlds are still there. The entire structure borrows the symbol collection system from Slurpy, built around four color-coded Collectors rotating above the grid. Two are active at any time. Symbols with a clear path upward get absorbed by their matching Collector, pay out, vanish, and the grid refills from below. Then the left Collector exits, a new one enters from the right, and it starts again.

Each world adds a layer. Whale clears its column when nothing matches - a reset that opens space for fresh drops. Pipe lets Collectors reach past wall barriers. Fireworks turns every Grey House blocker into a Multiplier Wild. Tree spawns Forest mystery symbols into adjacent empty clusters. Volcano is the endgame: one Collector goes berserk, wipes non-matching symbols, stacks matches, and keeps refilling until nothing new lands. By the time all five are active, a single round can chain through multiple feature types simultaneously. Coin symbols (1x to 500x) feed into a Piggy Bank that stores unclaimed values between rounds, with a random chance to crack open and dump everything back onto the grid.

The bonus shifts to a 7x7 grid with 3 Super Drops. No world features here - instead, the Ultra Beast replaces all Collectors, pays every symbol on the grid at once, clears it, and refills. Ultra Beast activations don't cost Super Drops, so chains extend naturally. The X-iter option at 500x opens with a x10 global multiplier already applied, and since every Multiplier Wild stacks onto that global counter, the expanded grid with x10 as a floor puts the 10,000x cap within realistic reach from the first drop.