Gold Boom

Slingshot Studios swapped the stage-magic dressing of an earlier release for pickaxes and lantern light when it put together Gold Boom, sending a grizzled prospector named Doug Deep down a mine shaft in search of a payout. The five-reel grid is framed against a tunnel backdrop, with mine carts rolling along the top of the reels as a visual cue for one of the game's central mechanics, and the presentation leans into a straightforward digging theme rather than anything more elaborate.

Each of the five reels shows three symbols, and 20 fixed paylines decide how wins land. Low-value rewards come from 9 through A card ranks, paying 1x to 2x the stake for five matching symbols on a line, while the higher-paying set covers hard hats, lanterns, barrels, pickaxes, canaries and a skull-and-crossbones icon, worth 5x to 10x for a full line of five. A dynamite stick acts as the wild, substituting for every paying symbol and worth as much as 50x the stake when five land together.

The carts above the reels are where Gold Boom does its real work. One of five cart types can appear above the rightmost reel at random, and it only pays out once a wild lands directly beneath it; more than one cart can be cashed in on the same spin. Carts that don't activate shuffle one position to the left on every spin and disappear once they reach the far side without triggering. Between them, the carts can hand out an extra scatter held in reserve until the free spins trigger, wild multipliers of 2x, 3x or 5x, a full wild reel, a walking wild reel that shifts left spin by spin, or letters toward the Collection Prize. Gathering a complete set of MINI, MINOR, MAJOR or GRAND letters pays 15x, 50x, 250x or 2,500x the stake respectively, and a randomly triggered MAJOR or GRAND spin can hand out an entire set on a dedicated reel set for that spin only.

Landing three or more scatters sends the game into free spins, where mine carts start above every reel and a wheel decides which of four modes plays out: 20 spins built around Collection Prize letters, or 10 spins themed around walking wilds, wild reels or wild multipliers. Before the round begins, players can pay to adjust the wheel's result through the Upsizer, and multipliers picked up mid-round only apply to the line wins they're attached to. Extra scatters can retrigger the round, and once it ends there's an option to buy one further spin at a calculated price. A separate feature buy lets players pay 50x the stake to jump straight into free spins.

Gold Boom carries a default RTP of 96.14%, with 94.04% and 92.12% configurations also in circulation depending on the operator. It's rated high volatility, hits a winning combination on roughly 26% of spins, and pays out up to 5,650x the stake on stakes from 0.20 to 40 per spin. The mine cart mechanic keeps something ticking over on almost every base-game spin even between bigger wins, and the wheel-selected free spins modes give the bonus round a different shape depending on which one gets picked.