It's amazing what a single, surprisingly-fitting piece of music can do for a game. Take Robot Unicorn Attack, for instance. The original was wonderful. The remakes? All that really changes is the art and that single song.

Robot Unicorn Attack's latest target is Christmas. The 99 cent iPhone game is due to hit iTunes Tuesday with a snowy background, antlers, red nose and a green knit sweater for R.U. and one bitching piece music to which you can play.

I don't think I've ever heard "Christmas Time (Don't Let the Bells End)" by the Darkness before, but now I can't stop listening to it, holding my breath for those dog-calling, falsetto high notes.

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