@clonedzero: He isn't the new commander. He is just a temporary acting commander until they elect a new one. Thorne has been around since season one, and he has always been a colossal dick to Jon Snow.
Ugh I remember just after defeating the gargoyles, I had an invader guarding the key for the Lost Sinner torches (which was why I was there in the first place) surrounded by those, 7(?) dogs. On top of that, I was carrying all those souls. After going up and down the ladder, trying to egg him into a fair fight I eventually had to pick off the dogs while dodging him, then proceed to destroy that coward. It's always incredibly satisfying when someone tries so hard to get the best of you in an underhanded way and you get to thoroughly put them in their place.
Of course, there are items that would have made that much easier but this was more satisfying. Basically, invaders annoying you? Step up your game. This is Dark Souls.
I hate to rain on your parade, but that was a NPC. That was a scripted invasion.