I feel so bad for the Gray Prince (SPOILERS)

[rat]

Poor guy, found out he's half vampire. And now he's super depressed. I'm in a match with him, and he's just telling me to kill him. But I can't do it, I'm just, staring at my screen. I can't kill a guy who's been nice to me ever since I've gotten there. I wonder if there's a mod to spare him.

[CullinB]

1) If you want to make him fight against you there is a way.
I read UESP and you can try "Frenzy" him.

http://www.uesp.net/wiki/Oblivion:Arena_(faction)#Expulsion
If you dislike the idea of hacking away at the Gray Prince while he's standing motionless and begging for his death, wait until after he talks to you, then cast a powerful Frenzy spell on him. As soon as you attack him, he will fight back. His war-cries will alternate between "Strike me again!" and "I've fought mudcrabs more fearsome than you!"

2)If you want to spare him, just put off your Raiment that will let you loose this fight.

Either way i did not test by myself, so try them by yourself.

[Ausfuhrung]

He's a racemixed human/orc abomination. Put him out of his misery already.

[Postal Merchant]

Originally posted by Арилиан:

He's a racemixed human/orc abomination. Put him out of his misery already.

Cyrillic name, comment checks out

[WhateverWorks]

The half-blood prince quest reminds me of that video where a bunch of people from South America did DNA tests, and they were all upset that they have European in them. Proud of who you are, unless the truth is more complex than you'd like.

[Drunkenstein]

Use poison then it will be quick.