Money Pipe Slot by Mancala Gaming

Pumpjacks rock under a hazy amber sky, steel platforms sit on lakes of crude, and the reels are bolted into a heavy industrial cage edged with yellow-and-black hazard tape. The whole thing reads like a 1970s Texas oil rush rebuilt as a slot cabinet, with the glossy molten-gold "MONEY PIPE" logo sitting above a brass "Hold and Earn" plaque.

The base game runs on a tight 5x3 with 20 fixed lines. Two tiers of multiplier Wilds do the heavy lifting: an X2 doubles any line it joins, an X3 triples it. The top symbol, a moustachioed oil tycoon, pays 5,000x line stake for a five-of-a-kind, which is a huge per-line ceiling for a game this volatile. Cash-value oil barrels print numbers on their face (20, 40, and higher) and pay scatter-style from any single landing, scaling up to 1,000x for five anywhere on the grid. Worth knowing before you spin: hit frequency is only 11%, so dry stretches are part of the design.

The whole game is built around the Jackpot Bonus. Land 6 or more Jackpot symbols in one spin and the reels lock into a Hold and Earn round. You start with three respins. Every new Jackpot symbol that lands resets the counter back to three, so a single late-arriving symbol can extend the round considerably. Each held symbol carries a fixed prize value, and the round ends when the respin counter hits zero or all 15 positions fill. The UI shows four named tiers across the top - MINI, MINOR, MAJOR, GRAND at 500, 2K, 5K, and 20K coin equivalents - but the underlying math actually carries five prize values (5x, 25x, 100x, 250x, and 1000x your bet), with the top tier almost certainly tied to a full-grid finish.

If you'd rather skip the wait, the Buy Bonus drops you straight into Hold and Earn for 40x your stake. The base game feeds the bonus, and the bonus is the whole point. Released August 2023 by Mancala Gaming.