I absolutely annihilated everything in the arena . . . until I tried Mirror Mode. Then I got slaughtered. Horribly! The last time I tried it, we hid in the back of one of the trains on the Pain Train map, creating a choke point that worked well. Then the very last Sim-Shep suddenly appeared behind me and took me out with a single blade to the back. I'm going to try giving Garrus and Ash the Typhoon and seeing how well they do then.