Rainbow Riches Race Day Slot by Light & Wonder

Five race tracks run along the top of the reels, one for each horse symbol, and they are the thread that holds the whole game together. Land five matching horses on a spin and that horse edges forward along its track toward a prize pot at the end. Get one all the way there and it pays out up to 500x your bet. The board itself is a 4096-ways layout dropped onto a bright green racecourse, a crowded grandstand behind it under a blue sky, with the gold-and-red Rainbow Riches wordmark sitting above a rainbow-arc Race Day logo. The symbol set is pure Irish good luck (four-leaf clovers, horseshoes, mushrooms and harps) sitting over the J-Q-K-A card royals.

Every win tumbles. Winning symbols clear out, new ones fall into the gaps, and a single spin can chain several pays in a row while the horses keep collecting toward their pots between cascades. The Wild fills in for the regular paying symbols only, so it never stands in for a horse or a Grand Derby scatter. That keeps the race honest, since you have to land the actual horses to move them.

Four or more Grand Derby scatters open the bonus, and it drops the fixed-spins idea entirely. Instead the round runs until one horse crosses the line and wins the race, however long that takes. Each pot starts at 10x your current bet, and during the feature you can pour extra funds into the pots to fatten the payout the leading horse will eventually claim, with win multipliers stacking on top. It is a different rhythm to most racing slots, where the bonus is a fixed bundle of spins. Here the finish line decides when you are done, and the running total in the pots is the number you are actually chasing.