Relic Entertainment has been following an odd progression with its Warhammer 40,000 games. In the first one, the real-time strategy title Dawn of War, you built bases and controlled dozens of units at a time. Rather than increase that scale in Dawn of War II, Relic actually went in the opposite direction, focusing on small squads and doing away with base-building entirely. Space Marine is almost the punchline to a joke, since now we're down to a single character in a third-person action game.

Players fill the boots of Titus, a captain in the Ultramarines chapter of the Space Marines. He and his compatriots are tasked with landing on Graia, a Forge World that has been all but conquered by the Orks. Your initial objective is to keep a gigantic Titan fighting machine out of the Orks' hands, but as always the situation quickly becomes more complicated. It's not spoiling anything, really, to say that Chaos eventually becomes involved.

If you didn't understand any of that, Space Marine might not be as interesting to you. The game is above all fan service; while you can enjoy it without appreciating Warhammer 40,000, half the fun may be witnessing fully-realized versions of things you've previously only read about or seen from a distance; the immensity of a Forge World, for instance, or an Imperial Guard army in action. More directly, though, the game is bent on making you feel like a Space Marine. Titus' armor is so hulking, for example, that it restricts his speed, even when he's sprinting, but this is more than made up for in the sheer destructive power put in your hands. Ammo is plentiful, and just about all of the available weapons will slice through Orks like a hot knife through butter.

This is rather important, since you may be facing a dozen or more enemies at any given time. To cope, the game uses a great control scheme that fluidly transitions from ranged combat to melee, the latter of which is arguably the core of the experience and a Space Marine's specialty. Button-mashers are severely punished, for the record. As indestructible as Titus might seem initially, combos are essential to surviving close combat, not to mention the rest of the game.

The need traces itself back to Relic's cover mechanic – or rather, the lack thereof, which helps push players into the fray and distinguish Space Marine from titles like Gears of War. In theory it should still be possible to hang back and pick enemies off at a distance, but to counteract this Relic has designed the game such that the only way of recovering health is through execution combos, or more rarely by entering Fury mode. Either way, much of Space Marine revolves around a delicate balance between mass slaughter and safely executing foes.

In practice this can have mixed results. It certainly accomplishes the objective of encouraging intense, close-quarters fighting, and the executions themselves are grizzly spectacles that feel right at home in Warhammer. Single-player fights can sometimes become mechanical though, especially since you may end up in frustrating scenarios either carefully setting up executions, or facing guaranteed death because you're low on health and you'll be gunned down before you can even approach an enemy. A greater problem is that none of the executions can be interrupted – during my playthrough, far too many deaths happened because I was locked into an animation during which someone finished me off.

All told the 8- to 10-hour single-player campaign is satisfying, but mostly because of its setting and originality, not because of smooth gameplay or clever level design. If people remember Space Marine it will probably be as a result of its multiplayer modes. On the surface, these boil down to simple 16-player deathmatch and capture-and-hold variants. The twist is that players can choose between three different classes, each of which requires a fundamentally different play style that compliments the others. The game furthermore uses a Bad Company 2-style unlock system, opening up new gear and customization options as a person advances in levels. This alone would probably assure some longevity, but Relic is also promising a free co-op survival mode in October. Should the developer live up to expectations, there may be plenty of reasons to keep coming back to Space Marine.

With multiplayer in tow, Space Marine represents a pretty solid foray into third-person action, particularly for a developer which founded its reputation on real-time strategy. My dire wish, though, is that when Relic next returns to Warhammer 40,000, we get something with a grander scale more befitting Games Workshop's universe.