All I need is a reason for Damon to be particularly unstable or vengeance-minded, and someone is bound to die. It would be fun to have Chris around for some vampire violence of some kind. If nothing else, I expect he'll be pleeenty unstable the next time I canon bump him.

Or maybe if he keeps butting heads with Starscream or something, he'll end up plotting against him. He knows Chris hates that guy. >)