The Dog House Slot by Pragmatic Play

Before free spins start, a 3x3 grid of barrels determines how many you get. Each barrel reveals 1, 2, or 3 spins, totaling anywhere from 9 to 27. That randomness sets the ceiling for everything that follows, because the round's entire value depends on how many sticky wilds you accumulate - and more spins means more chances to fill the center reels.

Wilds land exclusively on reels 2, 3, and 4, each stamped with a 2x or 3x multiplier. During the bonus, every wild that hits locks in place for the rest of the round with its multiplier preserved. The math on those multipliers is additive, not multiplicative - two 3x wilds contributing to the same payline give 6x, not 9x. Three 3x wilds across the center push a single line to 9x. Fill all three middle reels with sticky wilds early and the remaining spins just print, since every symbol combination connecting reels 1 and 5 through that wall picks up the stacked multiplier. But scatters are stripped from the reels during free spins, so no retriggers. What the barrels gave you is all you get.

The scatter is a jewelled paw print limited to reels 1, 3, and 5 - three of them pay 5x instantly and open the bonus. Paytable peaks at 37.5x for five Rottweilers before multipliers. The Shih Tzu, Pug, and Dachshund step down to 25x, 15x, and 10x. Collar and bone fill the mid-range. Royals sit at the bottom where they belong. None of these numbers look like much on their own, which is the point - without wild multipliers boosting them, even five premium symbols feel flat. The wilds are doing all the lifting.

Four cartoon dogs perched on a wooden kennel against a bright suburban yard, with 20 fixed paylines running across the grid. No bonus buy on this original release, so the base game is pure scatter-hunting between bonus rounds. The Dog House series has expanded significantly since this 2019 entry - Megaways versions, higher volatility variants, bigger max wins - but the sticky multiplier wild template started here, and the binary nature of the bonus (either the grid fills and explodes or it gives you 10x and moves on) is still the defining feel of the entire franchise.