What if spiders had lightsabers is an impeccable premise for a game, and Spiderheck delivers on that premise with aplomb. It's an arena fighting game geared towards couch co-op and couch competition, but there's online play and single-player modes too. Yesterday's "THE TRIALS OF JAZEPS" update added new difficulty levels to wave survival, as well as custom trials you can send to your friends.
It also chucks in some new maps with portals, because the only thing better than a lightsaber-wielding spider is a lightsaber wielding spider suddenly emerging from a portal.