In the N7 armor from Mass Effect, with the Omni Blade. Cause who needs the guns when you're a Sentinel with both Tech & Biotic powers! (I was in my play through at least).
Unfortunately, I haven't managed to do this outfit in fursuit yet XD

The original version link also has a variation without the wings, to show more of the background.

Original:
http://www.furaffinity.net/view/14417201/
http://dyyor.deviantart.com/art/Iron-Artist-Day-54-Nightdragon0-Cosplay-479660916