Unfortunately not as good as Supreme Commander, but the original Supreme Commander is easily the hardest RTS game to live up to. It's an average sequel with the same concepts and mechanics as the original, but the game lacks the scale and a lot of the creative command, control, tactics, and strategy that made the original game so amazing and special in the first place.
Still, it's worlds apart from the regular cookie-cutter RTS games that come out every so often. So if you and your friends require a new RTS with Steam capabilities to match wits against each other in, then look no farther than this. When you do pick it up, send me a message, I'm always interested to have a go at someone with this game.

A really cool take on Tower Defense, with 4 distinct and uniquely fun classes which you can play as. Numerous cool weapons and upgrade options. Buy it when it's on sale, though.

Like a furious combination of Team Fortress 2 and Smash TV, this game brings intensity, fun and you can't forget the BONUS TF2 ITEMS! If you enjoy fast-paced, hard-hitting FPS action then you'll love this game. Special abilities, unlocks, power-ups, the ability to construct turrets at hard-points, and various other ways to use points in each map against the enemy add a layer of fun strategic complexity to this otherwise straight-forward FPS.