The 30 seeded participants were called to step forward so the unseeded participants could challenge them. Needless to say, the unseeded participants would only choose to challenge those they were sure they could defeat. It would be detrimental to them to challenge someone stronger after all.
"Unseeded participants have to issue their three challenges consecutively. If you feel you can't defeat your opponent, you can surrender to conserve energy and avoid injuries. This will ensure you'll be in good condition during your following challenges. As soon as you surrender, I'll step in to stop your opponents from making another move," Lin Dong Lai said, "Now, I'll give the unseeded participants tokens to decide the order of the challenge. As for the 30 seeded participants, please step forward and stand in front of the people of your respective forces to make it easier for the unseeded participants to challenge you."