It's not unusual for developers to thrust animals into unusual settings. We've had monkeys trapped in giant balls, foxes piloting spaceships, and now - courtesy of Aqua Kitty DX - we have a cat at the helm of a submarine.

But don't call the RSPCA just yet, because Aqua Kitty has a serious job to do.

In a feline dystopia where milk has become rare and precious, cats are left with no option but to take the terrifying plunge beneath sea level - the only place on earth where milk supplies remain plentiful.

Tapping into an apparently rich vein of milk stowed beneath the waves, the milk miners work tirelessly to dig up pints of the good stuff, protected from the icky water by fishbowl helmets and adorable little astronaut-esque outfits.

But, to complicate things further, mechanical beasties roam the ocean depths attempting to intercept these milk miners.

This is where you come in, darting around in your submarine and protecting your dairy-craving chums from the marauding hordes.

Don't milk it

The game isn't a complex beast. Playing just like a sidescrolling shoot-'em-up from a bygone age, there's a pretty simple formula for success here - dodge enemy fire, and shoot the enemies who try to drag the miners from their milky prize.

As a shooter it's fairly ordinary, but its appeal is the hectic, plate-spinning nature of it all. Getting a flashing red alert on the screen, like some kind of distress signal on a superhero's gadget, means that at least one milk miner is in an enemy's grip.

Racing back and forth through increasingly ferocious mobs of enemies to free them soon becomes a very tense affair.

But that, essentially, is what will carry you through here. Everything moves and controls fluidly enough, not to mention the pixel art being absolutely beautiful in its vibrancy, but it's certainly a game better suited to short bursts of play.

Its very concept brings about two limitations - the playable area has to be small enough to effectively patrol, and the underwater setting doesn't lend itself to much variation.

As a result, if you're playing for longer than a few minutes, the waters of Aqua Kitty DX can begin to feel a tad stagnant.

New cat, old tricks

There has been an effort here to switch things up. While the environment itself doesn't change, the weather varies from glorious sunshine to moonlight-bathed blackness, and the difference is a clear one.

Add in an arcade mode, which has you spending gems on weapons and upgrades as you go along, and you'd think Tikipod had done enough to keep things fresh.

But there are none of the impressive set-pieces that many shmups dole out in abundance. Shooting enemies here is more of a means to an end rather than explosive moment of triumph.

And while there are boss fights, they don't seem impactful or frequent enough to provide any real spike in the excitement level.

The enemy designs, too, fail to excite. They're beautifully rendered, just like everything in the game, but they seem a little too safe and ordinary-looking to fit with the ingeniously bonkers concept.

However, despite these qualms, it's hard to argue that Aqua Kitty DX has appeal as a quickfire arcade game.

Having to defend the milk miners is a consistently tough and sometimes exhilarating challenge, and there's no greater feeling than prising one from enemy clutches at the last possible moment.

It's a game which is so excellent in parts, that it only serves to frustrate that some elements hold it back from being truly remarkable.

But for the crackers concept, gorgeous art, and ear-worming chiptunes alone, Aqua Kitty DX deserves a great deal of praise.