I had just killed Vahlok and was returning. Wanting more of a fight, I decide to jump down into the pit with the corrupted shades. On the way down I summoned Durnehviir, expecting a fight. But sadly, none was there. All 1-hit kills. With an elven dagger, Doing 17 damage + 25 frost damage.
But, Durnehviir followed me through to the other end of the pit.
It was badass to have a dragon stomping behind ya, and not trying to fry you into bacon...