Untouchable challenge agaist a Warchief and his captains. Custom challenge. I had one of the captains branded accidentally. It did make interesting, though.
MIDDLE-EARTH™: SHADOW OF MORDOR™ LEGION EDITION https://store.sonyentertainmentnetwork.com/#!/tid=CUSA00102_00
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The damage dealing routine for me is Wraith Blast, Flurry, Ground Finish (it's quite fast...