Derius was not suited for battle… at least according to him.
He despised violence, and he was also a very cautious Elf. Even his Original Magic, Absolute Insight, wasn't attack-based in any way. He had always preferred things this way.
Thus, when the youngsters had told him to leave the battle to them, Derius had agreed without even putting up a fight. He was actually relieved that he wouldn't have to fight. Preferring to be a spectator, he watched Ivan and Jerry work their Magic.
Ivan was able to merge his Flame attribute with his Wax Emperor's ability, in order to form his Bond Magic: Boiling Wax. He used this technique to raise the temperature to thousands of degrees. However, that wasn't all.
He was also able to harden his Wax, instantly freezing the enemies in a completely static state as the wax covered their whole bodies. Thus, the Corrupteds suffered a very brutal death.
'Impressive.' Derius thought to himself.