Some games are deceptively deep and complex. While on the surface they look like nothing more than one trick ponies, it's not until you invest some time that the real game shines through. This sums up Sony Japan Studio's The Last Guy perfectly, a PSN release that's essentially a frantic Pac-man-esque collection game with a survival horror twist, and a surprising amount of tactical play.

The plot in The Last Guy is exceedingly B-movie, with some kind of infestation of giant monsters causing the world's population to take shelter in whatever they can: buildings, cars, trees... you get the picture. These beasts are always on the move and will attack if they spot some tasty human meat roaming the streets, so the people of Earth need some kind of saviour - that saviour is you.

Viewed entirely from an overhead satellite image perspective you move about each area like Pac-man would if he'd escaped from his arcade cabinet and ventured forth into the real world. You're not entirely limited to rigid corridors like Pac-man, but the fundamentals are the same. There are certain paths you can go down and an awful lot of blocked areas and people (like Pac-man's yellow pills) to round up. Each stage has a time limit and a required number of citizens you need to take to the rescue zone. It sounds remarkably simple.

To begin with it is. You'll move through the first few stages with relative ease, rounding up the required number of stranded citizens well within the time limit, but things quickly change. As soon as the monsters you encounter extend beyond drone-like bugs and oversized brain-dead beasts you need to pay closer attention to what you're doing. Where you could previously zip about the streets and back to the rescue zone while waving to the monsters as you flew by, the new monsters will actually start attacking your rescued citizens who have formed in a queue behind you. They'll even eat you, and that's instant game over.

As soon as the monsters start becoming a real threat the whole game changes. In previous levels you could wander around with a tail of 600 or more civilians, bashing down barriers (barriers in the game require a certain sized group to be broken down) and freeing more citizens with ease (surrounding a building or object with a solid line of people will instantly rescue all that are hiding inside). But then, rather suddenly, you start to lose all your hard work when a monster storms in a scares half your line back into hiding.

The use of satellite images is rather clever

We're not saying that The Last Guy is the most tactical game ever made - it's not - but it does require more thought than you might think. With your guy having limited stamina for fast running (stamina bonuses are awarded for longer civilian queues), you'll have to have your wits about you if you're going to rescue people and stay alive, especially in the larger maps that require careful planning. The game gives you some help however. Dangerously placed pick-ups drastically alter the gameplay by freezing monsters and granting temporary unlimited stamina.

At times the game is overly punishing, with lengthy sessions being wiped out when a monster ambushes you. Even if you've managed to rescue the required number of civilians and taken them to the safety of the rescue zone, if you're killed while trying to round up more it's game over. The satellite imagery is also more problematic than we'd have liked, simply because of the way the images have been taken. From the default view your guy often gets lost behind buildings and trees, forcing you to use a thermal imaging view that shows the road layout in more detail and pin-points civilian locations. The problem in this view however is that the monsters aren't visible.

For £4.99 The Last Guy is certainly worth a look, offering the kind of gameplay that you just won't find in full retail releases. The low price also reflects the brief campaign, although it's perfectly feasible that new areas could be added via DLC. If the idea of Pac-man surviving a monster invasion sounds good, add this to your growing PSN collection.