Money Train 3 is the third instalment of Relax Gaming's flagship series and builds on the mechanics that made the original and its sequel underground hits among high-variance slot players. The western setting returns — this time styled as a retro train robbery — and the Money Cart bonus round remains the defining feature of the game.

The base game operates on a 5×4 grid with forty paylines. It functions as an appetiser: wins occur, the two sets of reels spin in opposite directions for visual interest, and occasional collector symbols appear on the left set of reels. The real purpose of the base game is to trigger the Money Cart bonus, which arrives when three or more scatter coins land simultaneously.

In the Money Cart bonus round, five reels and three rows fill with special symbols over a guaranteed three spins. Each new special symbol resets the spin counter to three. The special symbols include persistent coin values, multipliers, payer symbols that collect neighbouring values, and persistent symbols that stay in place for the duration of the round. A series of new symbols in the third iteration — including the Necromancer, which collects all coin values and multiplies them — significantly increases the ceiling compared to earlier entries.

Three money bag symbols landing simultaneously trigger the Super Money Cart, which carries a separate maximum win of 100,000 times the stake. The Buy Bonus feature, where permitted, allows direct entry into the Money Cart at 100x the base stake.

Money Train 3 is a polarising slot. Sessions without the bonus are genuinely dull, and the bonus can terminate with a modest result if only low-value coin symbols populate the grid. When a Necromancer or Payer appears in a well-populated grid, however, the round escalates rapidly into territory that justifies the game's cult following.