Hall of the Mountain King Slot Overview
Hall of the Mountain King is a 5x3, 20-payline slot built by Quickspin, inspired by Edvard Grieg's famous orchestral composition from 1875. From a math perspective, the numbers here are solid: 96.29% RTP, high volatility, and a max win of 7,326x your stake. Bets range from 0.20 to 100 per spin.
What separates this game from a typical fantasy slot is the three-stage progressive Free Spins bonus. Each level escalates in intensity, upgrading symbols, collecting Whirling Wilds, and boosting multipliers up to 15x. The orchestral score builds alongside the mechanics, reaching Grieg's famous crescendo at the final stage. I found the layered approach ambitious, though the complexity may put off players who prefer straightforward gameplay.
Symbols and Paytable
Five troll characters make up the premium tier. Mountain King pays 40x for five on a payline, matching the Wild. Troll Queen sits at 20x, Female Troll at 15x, Male Troll at 10x, and the Ork at 7.5x. Low-value card suits (A through 10) pay between 6.25x and 2.50x for five of a kind.
Wilds appear stacked on the reels. They substitute for every symbol except the Hammer Scatter, and each wild landing activates the Multiplier Meter on the left side of the grid. From a paytable structure standpoint, the gap between premium and low-pay symbols is wide enough that the Symbol Upgrade feature in the bonus carries real mathematical weight; removing low-value symbols from the reel strips dramatically shifts the EV of every subsequent spin.
Symbol Payouts
Bonus Features
Landing 3 Hammer Scatters on reels 2, 3 and 4 triggers the Free Spins bonus. The round plays out across three progressive levels, each adding a new mechanic. I think of it as a compound EV escalator: every stage feeds value into the final payout spins.
Level 1 runs the Symbol Upgrade. Each time the Mountain King smashes a block on the upgrade meter, one low-value symbol is stripped from the reels and replaced by stacked premiums. Multiplier blocks can also be smashed here, pushing the Multiplier Meter ceiling from 5x up to 15x. You progress once all blocks are destroyed.
Level 2 shifts to Whirling Wild collection. Up to 6 wilds are freed from stone blocks and stored above the reels. Level 3 gives you exactly 3 spins where those collected Whirling Wilds drop into random positions, combined with your upgraded symbols and boosted multipliers. The numbers tell you everything: 15x multiplier, stacked premiums, and 6 extra wilds on a 5x3 grid with 20 paylines. That final stage is where the 7,326x max win lives.
Bonus Buy Options
Wilds on the reels activate multiplier values from 1x to 5x in the base game. Each wild in a winning combo adds one level to the meter.
Free Spins - Level 1 (Symbol Upgrade)
Triggered by 3 hammer scatters on reels 2, 3 and 4. The Mountain King smashes blocks to remove low-value symbols and replace them with stacked premium symbols. Multiplier meter can upgrade to 15x.
Free Spins - Level 2 (Whirling Wild Collection)
The Mountain King smashes Whirling Wild blocks to collect up to 6 wilds, held above the reels for later use. Multiplier meter continues upgrading.
Free Spins - Level 3 (Whirling Wild Drop)
Final stage with 3 spins. Collected Whirling Wilds drop onto random reel positions each spin, combined with upgraded symbols and boosted multipliers.
RTP, Volatility and Max Win
96.29% RTP sits slightly above the industry average of 96%. House edge is 3.71%. Volatility is high, which aligns with the bonus structure; you are essentially front-loading dry spells in exchange for concentrated payouts during Level 3 free spins. Base game wins can still reach 4,000x thanks to stacked wilds and the 5x multiplier, but realistically the big numbers come from the bonus.
One criticism: there is no bonus buy option. Players who want to skip directly to the three-stage feature have no shortcut. Given the high volatility and the fact that the base game can drag during extended sessions without scatter hits, this is a notable gap. Not everyone will have the patience for the natural trigger rate.
