On the face of it, Great Blue is a fairly simple title – it has a decent jackpot but the visuals and sounds aren't particularly fancy, it doesn't have an expensive movie license associated with it and the gameplay is pretty standard.

Yet, despite all that, Great Blue has built a name for itself as a real favourite amongst Australian pokies fans. We take a closer look at the game below to see if we can figure out why so many people have fallen in love with it.

Despite having graphics that occasionally recall Finding Nemo and other times look more like they're based on Free Willy, Great Blue isn't associated with any license and is an original title.

This is a good thing, because pokies that rely on name brand recognition of their media license date quickly and they are sometimes put together hastily and sloppily. None of that is true of Great Blue.

Reel icons include bubbly versions of A, K, Q, J and 10, plus seahorses, turtles, oysters, starfish and whales. It all comes together to create a consistent undersea theme that instantly feels familiar.

With its inconspicuous but attractive graphics, Great Blue is just a fun slot to play. It's loads quickly, works well and has all the features you could want, making it a game you'll probably come back to time and time again.

If you're looking for answers to the question of why Great Blue is so popular, the 10,000x line bet jackpot is as good a place as any to start. In theory, it's possible to up your line bet to hundreds of AUD...which would make for one heck of a jackpot.

At the other end of the scale, it's possible to play using just one cent per line. Right off the bat, we can see that Great Blue is just as suitable for penny slot fans as it is for high rollers who can't enough action playing pokies.

The bonus round is just spectacular. Like its frosty cousin, Penguin Vacation, the game offers up to 33 free spins with a multiplier of up to 15x. Clearly, no matter how many losses you may have faced before getting there, this bonus round is capable of replenishing bankrolls with ease.

Whatever the value you're playing with, you'll find that there's often a long time between wins. Is this a factor in why Great Blue is so popular? We suspect so. A drought is often a good indicator that a bonus round is coming up, which is why players will sometimes stick with a slot they appear to be losing on.

And Great Blue's bonus round really is quite something. In fact, we'd go as far to say that it's one of the best you'll find on the market. And THAT, despite the volatile nature of the game, is what we think is the real key to its success.

We'd recommend giving the game a try in free play first, just to get an idea of how often you can expect to experience payouts, but we're almost sure you'll be back to play with real money.

If you're wondering why this cartoony undersea slot is so popular you need look no further than its jackpot and bonus round. With 10,000x your line bet up for grabs and a round of up to 33 free spins with a multiplier that gets as high as 15x, it's plain to see that players stand to make some serious cash swimming with the whales. Be prepared to hang around a while before you reach a bonus round but, when you do, it's unlikely that you'll be disappointed. There are fancier games out there but, still, this is never a bad choice when you're playing pokies online.