Money Train Slot by Relax Gaming

Money Train kicked off the whole thing. Before this 2019 release, Relax Gaming wasn't on most players' radar; after it, the Money Cart bonus became the template every high-volatility studio tried to copy. The original is rougher and simpler than the sequels - and that's part of why it still holds up.

The 5x4 grid sits inside a wooden Wild West wagon, with brass fittings, hanging lanterns, and tumbleweeds drifting past the rails. Cowboy gang members fill the high-pay slots: a sheriff in a black hat, a grim outlaw, a banker, a conductor. Low-pays are card royals carved into weathered wood. Distant mesas blur in the desert haze behind the reels. The base game runs on 40 fixed paylines with stacked symbols and a standard Wild substituting for everything except the Scatter, and honestly, that's all the base game does. Land 3 or more Scatters and you're into the bonus. That's the entire point of spinning.

The Money Cart bonus is where this game lives. The reels transform into a moving freight wagon and you start with 3 respins. Each new persistent symbol that lands resets the counter back to 3, so every fresh hit buys you more time. Six bonus symbol types do the work: coin values that just sit there with a multiplier, Payers that dump their value onto every matching position on screen, Collectors that sweep up every coin value and add the total to your pot, and persistent versions of both that lock in for the rest of the round. Then there's the Widener - exclusive to the original Money Train - which physically expands the grid by opening additional reel columns, giving more room for symbols to land. Sequels dropped this mechanic for different expansion tricks, so it's a quirk that only this first game has.

The bonus ends when respins run out. Hit the right combination of Persistent Collectors and stacked Payers in a widened grid and you're chasing the 20,000x cap, which felt enormous in 2019 (sequels later pushed to 50,000x, 100,000x, and 150,000x). For UK players the direct buy is gone, but elsewhere 80x your stake skips straight to the Money Cart. Worth it? At a 25% hit rate on the base game and a bonus that swings from 5x dud to 20,000x monster, the buy is mostly about whether you want to gamble on bonus variance instead of trigger variance. Same volatility, just a different way to feed it.

Compared to what Relax Gaming built later, the original feels lean. No special modifiers, no second-tier bonus, no extra round behind the round. Just a base game whose only job is finding Scatters, and a bonus engine that became an industry blueprint.