Coldfire Keep

Every moment I've spent with Coldfire Keep has been a combination of tension, bewilderment, wall-punching fury, and unadulterated satisfaction.

It's an unforgiving first-person dungeon-crawler, as popularised by Ultima Underworld and Dungeon Master, and recently rediscovered by Legend of Grimrock.

It's not for the faint-hearted. It's a bit fussy, and it will have you howling in frustration, but it's also a damn good RPG that you'll keep coming back to if you're into that sort of thing.

If you know any of the games I mentioned earlier then you'll be right at home with Coldfire Keep. You travel through dungeons, one grid square at a time, turn at right angles to navigate the maze-like corridors, and engage in combat with the sorts of foes regularly found in fantasy settings. Still none the wiser? Check out this hands-on video on AppSpy.

Though there's the option for your movement to be controlled by virtual buttons, the default control scheme is based on swipes.

You swipe up on the screen to move forward, double-tap the floor to run, swipe left and right to turn accordingly, pinch to look at the ground before you, and perform a two-finger swipe to strafe sideways.

It's quick and easy to use after ten minutes, but whenever you're asked to poke a button everything slows down.

The controls are particularly fiddly during combat, particularly when the 'attack' or 'magic' buttons fail to respond - though it's important to stress that I'm reviewing the iPhone version, and the iPad one probably doesn't suffer quite as much, if at all.

The combat otherwise is decent fare. You attack using the weapons you find throughout the keep, heal your party using magic, and so on. Rather than being turn-based, it's reminiscent of the Active Time Battle system from the Final Fantasy series, in which an invisible bar refills before you can strike.

When you start out even a humble rat will kick your butt, and when you happen upon a pack of them for the first time it fills you with dread. When you first encounter a goblin, cold sick fear overcomes you. You learn early on that the things dwelling in Coldfire Keep are not to be trifled with.

As this is an RPG, you'll be gaining XP for completing tasks, exploring, and killing the bad guys. When you've got enough XP, you level-up, and your abilities improve. If you need to improve you can always warp back to a previous point and begin the grind anew.

More exciting than the fisticuffs is the exploration and puzzle-solving. Each floor of the dungeon is sizeable, but most importantly it twists and turns and is filled to the rafters with traps and secrets.

Just picking up an item can kill a party member, as it may be booby trapped, but it also might be the figurative (or literal) key to progressing to the next area too.

Puzzles with levers and pulleys and pressure pads morph the pathways in the keep yet further, and although the core ideas for the puzzles are standard they're executed well and that's what counts.

Then, suddenly, just as you think you're pretty smart and totally tough, you take the wrong path and run into a mystical creature that wipes out your party in a few moves, or you die of starvation because you forgot to feed your heroes.

You're rarely given a moment to feel smug. Danger's never far away in Coldfire Keep.

But that tension is exciting, and the thrill of eventually overcoming the game's stern challenge is hard to top. Every RPG fan with an iOS device should buy this game.