You dont even kknow the other side of story, none of us know. It could be OP exxegarting stuff to jjustifies his reason when he probably didnt even bother to send tells to the lv50 guy. People have known to twist stories to favors them, i personally do not believe anyone would kill normal mob and leave the NM alone, i could believe he kills everything for aachievement purpose, but leaving NM alone is probably the story OP made to get us to side him.