@otouniisan
There actually is reason to believe the lightning isn't his power. The whole conflict with Ulmander led to MC learning that magic requires training your body. It's why the magical beings all dress scantily: to show off their effort, which equates to power.
@Xxjuggernaut@otouniisan on that note we are in a fantasy world with demons. I just assumed the king was immortal (he did call the mc a “brat”) and the arrogance he shows as a character (to me at least) suggests an older person who’s used to power.