I assume just by being the main death knight. He was able to make other death knights powerless before him the other abilities are mainly tied to his spells.
Resurrection is on undead, Power Nullification will work cause it has range along with soul manip, Soul manip is through various methods but Frostmourne's soul rip is the one to look out for, mind manip isnt acclible unless Aang is an undead somehow or grabs the helm, Disease manip is an average DoT, and blood manip is usual DK blood manip
He has a fairly sizable AP advantage, but everything else is dog shit as far as Arthas is standing, especially if he gets close enough to love tap with Frostmourne.
Yea hes not gonna try to convince the lich king to give up the fight?
