In the first place, a duel is a sacred way of expressing competitiveness for the knights. It is a matter of honor.
However, no matter what, there will be those who would abandon their honor just for the satisfaction of their ego.
We call those cheaters. No matter what, there will be those who will try to twist the rules of duel or just basically ignore the rules.
And, of course, to counter those types of situations, a referee is a must.
"Yes. However, let me set the conditions. If he wins the duel, I shall forgive him for his deeds; however, if I win, I shall remove both his arms with the Seal of Grafted. Do you accept, Knight Heschel?"
"Yes, I accept."
The moment I stated the conditions of the duel and the other side have accepted it in the presence of everyone, the duel was already appointed, and there was no returning back anymore.
"Then we shall commence with the duel on the sparring arena."
