Mental strength is notoriously difficult to cultivate, and only individuals can do so. Once a cultivator consumes too much mental energy, the consequences are quite severe.
Whether comprehending the Heavenly Dao or cultivating at their level, both required the consumption of mental energy. Usually, aside from taking medicinal pills, one had to rely solely on resting and meditating independently to recover and enhance mental strength.
Yet Xiayu no longer needed to do any of this.
Chapter 448