But the game's technical achievements are only a part of the picture. What Ready at Dawn has clearly done (with a little help from Sony's San Diego studios) is analyse what makes God of War work and then find ways of making that fit on the PSP. The fact that the camera has always been CPU-controlled probably helps, but somehow Chains of Olympus maps all the complex, combo-based combat mechanics, the use of magical attacks and the dodging, jumping and climbing manoeuvres of the PS2 games onto the four face buttons and two shoulder buttons of the PSP. The amazing thing is how quickly you make the adjustment, learning that different combinations of the shoulder and face buttons will pull off particular attacks, the rapidly clicking both shoulder buttons and pushing the analogue nub to initiate a dodge. It feels natural - and this proves crucial to making the game a joy to play.
All the elements of the superb God of War gameplay are there as well. Brutal brawls featuring multiple weaker enemies? Entertaining block and switch puzzles? Tricky fights with one or more giant-sized foes? Medusae? Climbing sections? Columns to be knocked over and huge siege-engines to be fired? All present and very much correct. Admittedly the game is a little light on weapons, but Kratos' legendary chained Blades of Chaos are still as flexible and powerful as ever, while the new addition - a gauntlet that packs a god-like punch - is just brilliant. You can almost feel the crunch of shattered zombie skull. The gory finishing moves are back, and once again show how - used the right way - those normally irritating quicktime event sequences can actually add something to a game. The latest magical attack, a pounding from a fiery Efreet, is another one to treasure. In fact, the game even manages to throw in a little off-screen slap and tickle - where does lusty Kratos find the energy?
Best of all, Chains of Olympus captures the relentless pace and interesting narrative hooks the series has become famous for. A prequel, the game takes place in the days before the first God of War, with Kratos up against mysterious forces from the underworld when the Sun god is put out of action. All the same, Chains feels like more than just a side-story. Once again, it delves back into the haunted Kratos' blood-drenched life and fills out a little more of his character, reminding you why of all the myriad hard man game characters introduced in recent years, this one stands out as something special. Meanwhile, the pace is nigh on perfect, spacing high-octane sections of combat with more tranquil sections of puzzle-solving, and ensuring that each chapter builds towards a suitably gigantic climax. And while I suspect Chains of Olympus is too intense a game for the daily commute, kudos to Ready at Dawn for placing checkpoints and save points just about regularly enough to make it possible to play the game in relatively bite sized chunks. That's ‘possible', but not ‘probable', because once you get started it's nearly impossible to put the thing down.