I know i'm 0-2 on new threads, but HEY! I picked this game up off steam last night to play with a friend and had a blast. It's a tower defense style game, and also gives you the control of a player which handles like a dungeon crawler. your player levels up and has pts to distribute to improve themselves or their towers and you also get gear.
Well worth the 15 bucks already IMO, but im sure it will go on sale soon enough.