Hello,
this exploit is quite old but it's still not fixed
in Ahn'kahet: The Old Kingdom are running mobs around named : ahn'kahar spell flinger
as a dk you can use control undead on them.
you might thing : so ? it's just a normal undead... NO!
this mob has a spell that will hit 50% of the hp of his target ->bosses get 2shotted with it
blizz won't fix this quickly so have fun using this in timewalking dungeons.
for the people that say this is not an exploit , i dont think blizz their intention was that you can 2shot a boss with it (or use 2dk's are kill them in less than a second)