I remember moaning about how dull Infinity Blade seemed after seeing it for the first time. Sure, it looked pretty (oh did, it look pretty), but the linear one-on-one fights, swipe-to-swing combat mechanics and limited navigation had me bad-mouthing the game before I'd really given it a chance. What's the point of having an amazing engine if you aren't going to do anything interesting with it? But after sinking a fair few hours into the game, I'm happy to admit I was too hasty in forming my opinion. Infinity Blade is not only a phenomenally attractive game, but also a surprisingly deep role-playing experience with an addictive quality that I never expected to take such a forceful hold of me.

The God King sits on a throne atop an ancient castle. This armour is white and regal, his heart is black and cruel, and his level is a staggering 50. A brave (or is it stupid?) warrior fights his way to the throne room regardless, intent on plunging his blade into the tyrant and freeing the denizens of the land from his brutal regime. Things don't quite go to plan. The King spawns the Infinity Blade from some otherworldly dimension, and proceeds to slay the virtuous warrior with a single blow.

Thirty years later, the warrior's son stands on a precipice overlooking the castle grounds. "I will avenge my father!", he cries - and so begins the first Bloodline. The idea is to fight your way through the King's underlings (who are all bigger and far scarier-looking than the King himself), and return to the chamber where your father was once slain. Don't expect to exact your revenge on the first attempt, however. Or the second, third, or fourth for that matter. The God King is fast and horrendously powerful; he'll kick your armour-clad arse before you can even put a scratch on his glorious suit of armour. You'll die, and the next thing you'll see is your son standing on a precipice overlooking the castle, vowing to avenge your death.

The hook is all in this cycle, the familiar grind that RPG players love so much. With each new Bloodline, your chances of slaying the God King improve. Each new lap of the castle yields more money and better loot, turning you into a more worthy adversary. Each time you die, you carry over your XP, items and weapons to your next Bloodline. Unlike Epic Citadel - the tech demo showing what Epic could do with the Unreal Engine on an iOS device - your movement options are limited. You can drag a finger across the screen to move the camera, but you never control your warrior directly. You can take different routes through the castle by tapping little blue swirls thatwill take you from one screen to the next - but there is a very clear cut route through the game.

Exploration is clearly not the focus here, though. Combat is. The mechanics underpinning the experience are incredibly simple: rock paper scissors with swords, shields and magic. Swiping a finger across the screen will swing your sword in that direction, but these attacks will be swiftly deflected without the right preparation. The idea is to 'break' your opponent first, leaving him open to attack. The easiest way to do this is to dodge incoming attacks. If your adversary swings right, dodge left. If he swings left, dodge right. Both can be achieved with a tap of the evade button lurking in either corner of the screen. Dodge enough times in a row (usually three), and you'll 'Dodge Break' your foe, after which you can unleash your counter attack. Much of the strategy comes from 'Parry Breaks', where you trace the line of your opponent's attack to launch an immediate counter attack.

Depending on what equipment you have equipped, certain magical abilities are also available to you in battle. After tapping the magic icon in the top right of the screen, you can choose which spell to cast by recreating the corresponding symbol with your finger. At first you'll simply be casting fire and ice attacks, but it isn't long before Heal and Shield spells get in on the action too, and the scope for strategy expands. A 'super' attack button lives in the top left of the screen, which as well as dealing a hefty amount of damage, sends your opponent into a dazed state leaving him open to a barrage of furious swipes.

Combat is entertaining enough, but it's the progression mechanics surrounding it that define the game. In addition to experience points, each fallen foe drops gold, which can be spent in an well-stocked item store. Here you can purchase swords, suits of armour and magic rings, all of which offer different skills and stat bonuses. I'm currently rocking a helmet with Gold++ and a sword with XPGain++, which is handy indeed, I can tell you. Each item has its own XP system too, meaning you can master a weapon for additional bonuses. A particularly obsessive friend of mine is looking to master every item available, which will take far longer than completing the game itself.

I reviewed Rage not that long ago, offering the rather bold claim that it was the "...best looking mobile phone game ever". Scrap that: Infinity Blade looks better. Strolling around the grounds of the castle - the epic citadel, if you prefer - presents gorgeous architecture and stunning vistas at every turn. Enemies sport intricate suits of armour, brought to life with textures that will make iPhone 4 owners swoon with delight. It still looks great on older models, but anybody with a retina display screen should snap it up purely to show off to friends with inferior phones.

Sure, in terms of the core gameplay (that being combat) you don't actually do a whole lot. You swing, dodge and cast the odd spell every now and again, and that's about the crux of it. However, the experience wrapped around these mechanics gives the game an alarmingly addictive nature. At £3.49 it might seem expensive nestled amongst all those 59p price tags, but for what you get - glorious visuals, solid combat and surprisingly deep role-playing features - it's well worth forking out for. Buy it safe in the knowledge that you're not only getting the best looking game on the App Store, but a fantastic little action RPG in its own right.