Since they were on the road, it was inconvenient to conduct experiments. Isaac thus focused on more theoretical Magic Books while also taking the opportunity to take stock of his own combat capabilities.
Don't be fooled by how badass he looked on the battlefield, wiping out several thousand Knights in an instant.
In reality, that was all accomplished through a ritual. It was filled with elements of luck and would be difficult to replicate.
His own actual strength was rather average.
With enough preparation, he could at most fight above his level against one or two Great Knights. Besides, he was currently a typical glass cannon Mage.
In terms of offense, he had Flaming Arrow for mid- to long-range combat, which was considered excellent for his rank as an Official Wizard. However, his true trump card remained the Demons created through Flesh Conversion.
