Mark of the Ninja.. was pretty cool. stealthy but not retarded "you were spotted ...game over"
smooth gameplay, nothing too fiddly, and like $5 on steam. Nice variety, enemies / map layout very open options (kill everything or nothing or just the ones in your way.)
Downsides, the controls are console ish in orientation, but the mouse can play a nice role, so you can overlook that mostly. It's kinda short, but it does have good replayability, better scores can always be had, special achievements are fun, and unlocks give new and interesting ways to deal with problems.
