Fictional gangsters rule. Fireball-throwing ninjas rule. So what better idea for a mobile game than one that combines both? Mafia Wars Yakuza is that game, and guess what: it rules. But let's not get ahead of ourselves.

The game is the follow-up to Digital Chocolate's two previous Mafia Wars games, and whisks the action over to Japan. You play Snow Dragon, the adoptive son of the Oyabun (head honcho) of a Yakuza gangster clan.

Trouble is, when the Oyabun dies, your adoptive brother Aki turns on you, which not surprisingly leads to a bloody quest for vengeance that involves dealing death and destruction to hundreds of minions before telling Aki himself what you think of him (by pumping bullets into him before cutting him to shreds with a big sword, obviously).

The bulk of the game involves running round isometric levels, shooting people with one of four big guns, which are unlocked as you progress through the game.

However, you also get to whip out a big sword for some ninja swiping, as well as shooting fireballs as a Power Attack once you've fought a few baddies. Fireballs weren't a regular feature of the Japanese underworld last time we looked, but they are quite ahead in Tokyo, so who knows.

The controls for Mafia Wars Yakuza are simple. Walk up, down, left and right, and press '5' to shoot at stuff. Being able to blow bits of the scenery apart is fun but can also have a more useful role, to help get to secret rooms for extra cash or health bonuses.

When enemies come within range, you start spraying bullets automatically, which means you just have to run around making yourself hard to hit, rather than having to concentrate on moving AND firing. It works well. Alternatively, when close-up you can press '0' to do a sword attack, or press '5' to lob fireballs if you've built up at least one Power Attack (which is shown by icons at the bottom of the screen).

If you've played the previous two Mafia Wars games, you'll notice the difference immediately. Here, the pace is much faster – there's less walking around looking for someone to shoot, and more strolling a couple of yards to be confronted with seven enemies waiting for a ruck. The shooting-to-walking ratio – a measurement we intend to patent for action games – is pleasantly high, in other words. And if you can dispatch a bunch of enemies at once, score multipliers give you a boost.

Also new are the boss characters that lurk at the end of each section of the game. Each has their own attack pattern, which you have to learn and combat to progress. They can be tough at first, but a little thought is enough to see them off.

There are two ways to play Mafia Wars Yakuza. You can work your way through the eight game levels one by one, being rated out of five stars for how well you complete them – getting a top rating requires killing all the enemies, and picking up the cash that litters the levels.

However, once you finish, you can also play the Tower Of Destiny, which is a 110-level building to fight your way through, until you've conquered it or dropped dead in the process. It certainly provides a hefty challenge once you've completed the main game.

It's hard to find quibbles with Mafia Wars Yakuza, other than the fact that the UK release of the game doesn't include Digital Chocolate's online features, which let you form clans and upload your Tower Of Destiny high score to compare against other players. Sadly, exactly when these kind of features will be implementable in the UK is out of Digital Chocolate's hands, as it's down to the operators.

In the meantime, this is one of the most entertaining action games we've played in a good while, blending characterful graphics, simple controls and fireball-chucking ninja gangsters. To not give it a go would be simply criminal.