Action packed with variety of enemies and Big Explosions however rarely any chance for tactics. Great Button Smasher.
You start with a chain sword and a standard issue bolter. If you are familiar with the Warhammer 40K universe then you'd know these are the most common weapons of the Spacemarines. As the game progresses you'd get access to more exotic weapons including Sniper Rifle, Grenade Launcher, and the "Thunder Hammer". But what's really fun is the Jet Pack. It allows you to unleash full fury upon the enemies of ;) . Its only available in certain missions though.
Action is kinda straight forward ... shoot on sight and hack and burn all the way through. Sometimes it feels a bit monotonous though but still enjoyable. You get all these weapons but you hardly need them. Its possible to pretty much complete the game with the items you started with. The boss fights are nice however it makes you feel the heat. :P
I liked the combat system. You can stun enemies and execute them (in slow-mo) to gain health during combat (stronger the enemy more is the health gained). As you keep killing enemies you fill up a rage meter. When unleashed you go into Fury Mode and become a uber killing machine. You do extra damage and also become almost invulnerable. But there are hardly any combos that you can do, mostly you'll find yourself smashing attack button.
Where the game could have improved was the storyline and variety in action. The story wasn't presented in a clear way. The characters are also hardly memorable. It felt the game lacked combo moves and style. Also I think the game could have allowed you to chose the class of Spacemarine (e.g. : Devastator, Tactical Marine, Assault Marine, or perhaps a Terminator) you want to play.
Overall, I enjoyed the game. For fan of the Warhammer 40K universe its a must try. Just don't expect something epic.