OK, lore wise:
Grand Widow Faerlina is the second boss (level ??) of the Arachnid Quarter in Naxxramas. Once one of the high-ranking members of the Cult of the Damned under Kel’Thuzad, in death she breeds and takes care of the seemingly endless amount of arachnids that swarm from the depths of the citadel. A master of poisons, she has a keen understanding of what makes mortals suffer. Huge loot table.
Herod The Scarlet Champion was a level 37 elite human boss in the Scarlet Monastery’s Armory. Dropped mail shoulders, mail helm and 2H axe.
Bloodmage Thalnos was a level 31 elite skeleton mini-boss once found in the Scarlet Monetarist’s Graveyard who was a blood elf mage prior to his undeath. Dropped an +int offhand and cloth shoulders.
Seems, Faerlina would be the closest/best/only character of those three with a link or similarity to Arthas. Thoughts?