The overpowering young man!

When Noah saw Roy scraping away his last line of defence as quickly as a rat eating cheese, his face contorted slightly and his eyes turned ruthless.

'If this continues, it won't be long before he breaks my shield and strikes me down. I can't let that happen.'

Even being struck by a trainee is humiliating for a rank-1 mage, let alone defeat. 

If Noah lost to him, he would become the laughing stock of society. 

He needed to win at any cost. 

That's why he decided to give "that" a shot. 

It was a skill he hadn't mastered and thus lacked control over, but it was the only move he had in his skill arsenal with which he could turn the tides of this fight in his favor and defeat Roy.

"You've forced my hand," Noah said as he secretly initiated the self-detonation of the shield enclosing him. "You'll now experience the true difference between me, an awakened soul herder, and you, a trainee!"