Sebastian's Show! Entering The Zone Of Glory!
Of all the skills that Sebastian had at his disposal, apart from the Doppelganger and Invisibility unique skill, the peculiar Rasengan skill was the most mana hungry skill that he had, even more mana hungry than his 1st unique skill.
The Rasengan could grow infinitely powerful so long as he had enough mana to feed it, and if he also had the technique to control it and prevent it from blowing up on himself which would easily make a top 10 most tragic magic stories.
Apart from his unique skills, this skill had the most potential in his opinion.
At this moment, Sebastian didn't have enough mana to make it as powerful as he could in his peak, but this was acceptable.
BOOM!
The blue ball of mana tore through the ranks of the Doom Destroyer mechs that were before it, throwing them into different corners while also tyrannically tearing their metallic skin away like it was mere rubber.