Wasn't jang uk born with the power of hwansu? That is what master lee hinted at park jin. In that conversation…
Hwansu is a level of power, when a mage can alter the nature of the elements (like, transforming water into fire). Uk is considered a genius bc he has the innate ability to easily learn how to control energy. That's thanks to being born under the King star.
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I'm trying not to think about it, but we'll have only 5 weeks of aos 🥲