Beat-'em-ups are, arguably, the purest gaming genre. The easiest way to sum it up is to ask yourself, how many other games make you leap up from your chair and goad your opponent like he just missed a World Cup penalty?

That said, Bloody Roar would miss the mark completely but for one lycanthropic twist. There are fifteen fighters in total, each with the ability to mutate into a savage beast. Transformations not only strengthen your attacks but also double the amount of moves you can perform. Usage is restricted by a hyper bar, and there's a subtle strategic element to knowing when best to expend your energy.

Going overboard with a hyper attack wastes valuable power and also leaves you vulnerable. Transformations can even be broken mid-flow by cunning counter-attacks, a superb way of turning the battle around with dramatic effect. Remarkably, it's a far less original feature that deserves most praise. Sega Saturn game Fighting Vipers pioneered cage combat as a way of confining the action into a small area.

Similarly, Bloody Roar's most exciting moments come from the Ring Out, when one swift blow sends your opponent crashing through the cage. There's something very, very satisfying about punching your nemesis through a wall and watching him get run over by a taxi. If the walls don't give way, you can use them to springboard right back at your foe.

Some arenas are even multi-tiered like the Dead Or Alive series. Nine arenas is a decent amount, but they're still sadly lacking in animation or detail. Combatants suffer from similar graphical problems, clipping being a frequent occurrence, but that pales into insignificance compared to the horrible character design.

Bloody Roar is dripping with so much Japanese eccentricity, from the spiky-haired heroes to the atrocious electric guitar music that is so unappealing. With the exception of a wonderful chameleon and a humongous elephant, there are far too many big cats and dogs with similar basic moves. There are a good variety of specials and combos though.

At first, it's easy to mistake the slower pace for a lack of responsiveness but it only takes a few goes to adjust. Sidestepping using the Left and Right triggers also feels a little dated at first, but soon becomes a lifesaving technique - especially when counters are awkward to pull off.

Bloody Roar Extreme on the whole has a real awkwardness about it. It's as though it's caught in the painful transformation between 2D and 3D, between 1999 and 2003. Short-lived fun but ultimately fails to go the distance against Dead Or Alive 3 and Soul Calibur II.

1. Multi-tiered environments
2. Being run over
3. Busuzima the Chameleon

1. Too many big cats and dogs
2. Ugly characters

Power
Arenas and characters lack detail, but beasts look impressive - some hyper moves are spectacular.

Style
Many beat-'em-ups benefit from a Japanese flavour, but this is too much. Music is earbleedingly bad.

Immersion
Achieving the Ring Out at the end of a battle is addictive and more fun than the fighting itself.

Lifespan
A decent number of characters and special moves will keep hardened fighters interested for some time.

Verdict This does all the right things but fails to excel in any area. There are better beat-'em-ups on Xbox.