Nidhogg 2
I bought this game for the soundtrack because I'm running a gaming music website called GameTestPlay, so sometimes I go out of my way to play games strictly for their musical value. And the beats on Nidhogg 2 are some of the illest I've heard yet.
The game itself is pretty bare bones and basic. At it's core it's a simple fencing game (like swords, not yardwork) where you make your way through a short level trying to stab your opponents.
There's little consequence of dying as you can always continue where you left off, so it becomes a matter of getting a high score once you've learned the mechanics and handful of weapons that are available, but I would just pick up the soundtrack instead.