Mysterious Butler:
After a long discussion with Lionel, I've decided that I'll find someone who can prove their strength by constantly participating in the Ceremony of Chaos and the Olympiad.
In order to keep track of your performance, you'll be getting a Proof of Battle whenever you participate in the Ceremony of Chaos or the Olympiad.
If you can get 80 Proof of Battle, you'll prove that you are worthy. Not too hard, right?