I've had a lot of fun playing this squad based RTS- and fell hard for the storyline tying all of the missions together. In DoW2, you fight a three-way war against Orks, Eldar, and Tyranids, as the Blood Ravens' space marine chapter. In Chaos Rising, you attempt to counter legions of traitor marines, as you and your sergeants are tempted by the forces of Chaos.
The one thing I didn't like about Chaos Rising was the fact that it was too short. I wish more Space Hulk missions had been crammed into that x-pac. These two games are definitely worth 13 bucks!
