Raze had originally used all of his mana to teleport the entire crowd from the arena and then further bring the Crimson Crane as well as his other allies to his side. While they fought against the Dark Faction, he had been building up both his Qi and mana. After all, he had used his Qi more than he thought during the fights he participated in.
Regardless, he had managed to regain quite a bit of energy earlier on, and because he saw what was happening, he decided to intervene. Using the Dark Edge Magic Sword Arts, he combined magic and Qi into his attacks, making sure to take out one of the most troublesome individuals in the Dark Faction. Raze had taken out Arkon with his strong attacks, using his element of surprise and superior powers, but it came at a cost. He needed to rebuild his Qi and mana all over again.