Fortunium is a 5 reel, 5 row, 40 payline slot from Microgaming that can be played from 10p to £125 a spin across all devices. With a steampunk theme, it comes with stacks of mystery symbols that can transform into another symbol as well as a Win Booster feature where you add a wager to remove low value symbols appearing in the Mystery Symbols feature. There’s also a Free Spins feature where you can get up to 5 Mystery Reels on each free spin.

Fortunium takes you to the golden city of opportunity and has a steampunk theme – set in a world of mechanical masterpieces and alchemical works of art, this game is best enjoyed in portrait mode on mobile/smartphone devices – it can be played on desktop and tablets too.

When it comes to symbols, you have clubs, hearts, diamonds and spades as well as plasma guns, airships, treasure chests and 2 characters: Maximillian and Victoria. Both these symbols are stacked 5 high with all other symbols appearing double stacked. There’s also a wild which replaces all symbols bar the scatter.

In terms of bonus features, there’s a Mystery Symbols feature which is played when Mystery Symbols land on the reels – they then open to reveal a randomly chosen low, high or wild symbol.

More important, Fortunium comes with a Win Booster feature which you decide when to use – it will cost you 50% more per spin (i.e. 10p to 15p a spin on minimum stakes) but it removes the chance for Mystery Symbol to reveal low value symbols. This means that the Mystery Symbols feature will then reveal only high value or wild symbols.

Fortunium also comes with a Free Spins feature which is played when you get 3, 4 or 5 scatters anywhere across the reels – you will then receive 10 free spins. Every additional scatter you land during the feature will give you an extra free spin.

Now, 3, 4 or 5 scatters will give you 1, 2 or 3 Mystery Reels on each free spin respectively – the Mystery Reels contain only Mystery Symbols meaning you could end up with 3 fully wild reels on every free spin! As a result, this will improve your chances of winning the maximum 800 times your stake on each spin.

Fortunium is a medium variance slot with balanced wins throughout – the Win Booster feature can be useful as it reveals high value or wild symbols only during the Mystery Symbols feature but it’s all about the Free Spins feature really. What you’ll be hoping for is to trigger it with 4 or 5 scatters to get 2 or 3 Mystery Reels on every free spin. If you like the steampunk theme, NetEnt’s Steam Tower and Yggdrasil Gaming’s Cazino Zeppelin are recommended.