Featureless Protagonist: Apart from his name being mentioned in the manual, not much else is set in stone about him.
Player Character: The guy you play as in Arena, and the first in the Elder Scrolls franchise.
Red Eyes, Take Warning: A reverse of this trope, as this applies to the monsters perspective if the hero is a Dark Elf. (See badass above)
The Unchosen One: Like the Imperial Agent, the Eternal Champion wasn't a hero of prophecy. They was only chosen in the sense that everyone else in the Imperial Court was either dead, brainwashed or in another dimension.
"With you died our last hope for justice. Tharn is now free to do as he will. It saddens me to see the beautiful land of Tamriel rotting from within. Goodbye, [player]. I wish you peace in the afterworld..."
"You were a fool to confront me, and now have paid the ultimate price. Even now my servants go to fetch your mortal husk. You will serve me well through my years as Emperor, once I have made you undead. Perhaps I will even let you retain some of your memories, so that the price of your failure has meaning to you..."
Large Ham: This guy was just plain fun to listen to.
Necromancer: If the above quote is any indication, he's quite capable of making people his undead thralls..