"Your curiosity will be the death of you...."
Kel'Thuzad, as expected of an Archlich, his appearance as a skeletal figure clad in tattered purple with gold ornamental engraving robes, often with a skeletal or ghostly appearance. He is often depicted with a crown or other headpiece suggestive of royalty or high status and two sets of chains that surround his skeletal torso.
The archlich manifested himself in his chamber of his flying ziggurat, Naxxramas, as he saw the invading raiders from the alliance, his glowing white eyes that shine from his skull face narrowed.
"You are no different than those fools from stormwind.. nothing more than pillagers."
He snapped his boned clawed fingers and summoned a small contingent of ghouls.
"Deal with the mongrel intruders.. I have more important matters to attend to." Just as he had appeared, Kel'thuzad banished.