The cosmos within a painting is an extremely profound realm in the cultivation of the Dao of Painting. It far surpasses the method of manifesting objects from a painting into reality through runes, the technique often called "bringing paintings to life."
The two are on completely different levels of difficulty. It is like comparing a technique of void evasion to a simple light-based method for rapid travel. To the uninitiated, they might seem similar, but only those who truly understand know how vast the difference really is.
In Zhuang Feiwu's memory, only two people in all of Huangzhou had cultivated their Dao of Painting to this level. One was his grandfather, Zhuang Mocheng. The other was the president of the Green Leaf Association, Cao Xiu. Both were renowned figures in the world of Dao of Painting cultivators. In terms of cultivation, they were powerful beings of the Earth Immortal Realm, towering above countless other cultivators.
