Opal Fruits is a six-reel slot machine. The first and last reels have three symbols, the middle four reels have five symbols each. You win if you have the same symbol one or more times on at least two or three consecutive reels from the first reel. That gives you 5,625 ways to win. The entire game screen fits exactly in the shape of such a Starburst candy. Just like the Fire Siege Fortress screen fits in the castle, for example. You can bet from € 0.10 per spin and up to and including € 20.
The symbols are a combination of playing cards and fruit symbols. The playing cards pay out from 0.1 times the bet for three times an 9 to 0.6 times the bet for six times an ace.
Pears, plums, watermelons and grapes yield a lot more. The grapes also pay out from a combination of two pieces. That will give you 2 times your bet. Six grapes is of course the most profitable: 50 times your stake.
That all seems like little, but thanks to the 5,625-ways-to-win mechanism it can go fast. Suppose you have a symbol three times on each reel. That already counts as 729 winning combinations (3 x 3 x 3 x 3 x 3 x 3 = 729). And so you can spin 5,625 combinations, every spin. Even more, because after a winning combination, the winning symbols on your screen are replaced by new symbols.
There are also two different Wild symbols. The normal Wilds and a x3 Multiplier Wild. The x3 Multiplier Wild multiplies all wins by 3.

Symbols with the letters F, R, E and E also spin on the reels. You probably already feel it coming. Once the F, once the R and twice the E is good for the bonus game. This bonus game consists of 10 free spins. Extra scatters do not result in extra spins, but they do result in a higher starting multiplier.
And during these bonus spins it is slightly different than in the base game. This is mainly due to the multiplier. Every time you win something, whether that be in a spin or after replacing the winning symbols, the multiplier increases by 1 step. Opal Fruits has no maximum multiplier, so it can go up to x20, x50, x100, to infinity.
Four scatters also give you 10 extra spins. Every time the multiplier is at 10 or a multiple of that, you also get 5 extra spins.
Once you've put together a nice multiplier and still have some spins, you take one multiplier after the other.