Make the theme his character. Make him look like a pathological liar, even if he's just an average one. This reminds me of the pranks my house played at Yale. Oh man, did we have a good time. If your opponent offers the olive branch, reject it, saying you don't trust him.
Negotiation is weakness.
If you have deficiencies, like draft avoidance or disorderly behavior, paper it over with patriotism, or blame it on youth. That would be a poor time to insist on accountability. I'll do what I can on my end to make sure none of it comes back to bite you. Winning is everything. Hate your enemy.