Su Yang didn't return directly, instead choosing a nearby valley, traversing the Spirit Liquid Lake at the bottom, and entering Storm Valley.
Heading to the Endless Starry Sky is for practical training, while inside Storm Valley, it's for personal cultivation.
Only personal cultivation, combined with extensive practical training, can rapidly enhance one's strength in the shortest time possible.
This method is not unique to Su Yang; even the Ten Great Sects, and those Su Yang recruited from Qinghe Academy, are employing this method for cultivation.
Those people, while at Qinghe Academy, start with basic cultivation. Su Yang provides them with some Elixir Pills to aid their cultivation. However, the cultivation outside is always the most basic.
Only when those individuals stand out and enter the World Melting Furnace do they formally begin cultivation.
