The Demon King's Duel of Intellect

Anos and his classmates search around Demon King Academy for the “Child of God.” While Anos’ comrades are fending off the attacks from the demons of two thousand years ago, Anos himself faces the King of Death’s Army Officer, Ziek Ozma, in a duel of intellect. In this duel, Anos must speculate who the “Child of God” is and make the correct guess. However, the number of times he can make his guess is limited. What was Anos’ answer, and what is Ziek’s motive ― ?!