Glowing Eyes.

It was apparent that it wouldn't be long before that teenager's side was killed.

He could keep three people at bay, but what about eight of them? At that time, he would have no choice but to accept his impending doom.

Ozul had no intentions of interfering, he was solely focusing on the teenager's technique and the saber in his hands. 

Each slash of his carried sparks of fire as the saber collided with other weapons. The teenager was using flashy moves, but he understood that they were probably the Spiritual Arts they had heard about.

'So doing specific movements generates those sparks? Is it not dependent on personal will and intentions?' 

Ozul tried to infer as much as he could from their battle and it seemed obvious that Spiritual Essence wasn't as kind as the Mana in their Realm. 

Mana could be manipulated solely with willpower alone. Chanting and movement played a small role initially. After that, it was solely reliant on willpower.