Set against a bubbling seabed brimming with aquatic life, the reels include lower value A to 9 symbols and higher value marine creatures. You’ll see a starfish and seahorse which award up to 10 times stake per payline followed by a striped fish which awards up to 16 times stake. The most rewarding standard symbols are the turtle and shark. Both of these award up to 30 times stake if you land 5 in combination.
The great blue whale is the game’s wild - it replaces all other symbols bar the scatter and offers mighty rewards of up to 400 times your stake if you get 5 on a payline. More importantly, if the wild forms part of a winning line with a standard symbol, that payout is doubled.
The pearl shell is the scatter - land 3, 4 or 5 of these anywhere on the same spin and you’ll pocket an award equal to 5, 20 or 500 times your total stake. You’ll also trigger the Pearl Bonus feature. Here you’ll start with 8 free spins with a 2x multiplier.
Pick from the shells to add more free spins and multipliers to your total. Get lucky here and you could start the feature with 33 free spins and/or multipliers of up to 15x. Landing 3 scatters triggers another 15 free spins, complete with the same multiplier – you can do this infinitely meaning there’s an unlimited amount of free spins up for grabs.
Great Blue Jackpot also offers a shot at landing life-changing sums courtesy of the progressive element - this can trigger at random on any spin. Once active, you’ll be offered a selection of coins. Land 3 of the same matching colour and you’ll win the associated Fish, Turtle, Shark or Whale Jackpot (in ascending order of value).
Playtech has kept things relatively simple here. The visuals aren’t as flashy as you’ll see in some similarly themed slot games but they work well enough. The bonus feature is pretty straightforward too. The combination of a large number of free spins and big multipliers is an alluring one though.
If you fancy dipping your toe into some volatile but enjoyable waters, then Great Blue Jackpot should appeal. Compared to the original, Great Blue, it has sharper graphics and animations – the gameplay is identical but has the progressive jackpot element of course. If you like the theme though, Mermaid’s Diamond by Play ‘N Go is good and also high variance.