Reign of the Seven Spellblades, Vol. 3 (light novel) — Bokuto Uno

Kimberly Magic Academy has lived up to its shadowy reputation in Oliver's first weeks as a student, with him and his friends encountering one mystery after another. Why did a garuda appear in the underground Colosseum? Why did the troll attack Katie during the entrance ceremony? As the final pieces of the puzzle fall into place, the stage is set for a deadly duel!