Yan Zhaoge's Northern Ocean Clone had been obtained from refining someone else's mortal shell. He was a Martial Saint from the start, his foundation solid as it would not be easy for him to switch to cultivating in other martial arts. Thus, he had not cultivated in supreme martial arts of the Jade Clear lineage like the Peerless Heavenly Scripture and the Cyclic Heavenly Scripture.
However, Yan Zhaoge had supreme martial arts suitable for him as well, causing him to grow stronger and stronger.
After solidifying his foundations with the Supporting Soaring Art had come a famous supreme martial art of pre-Great Calamity times, the Great Wilderness Fish-Roc Art.
It was the elite martial art for the human race in cultivating in the power of that mystical creature.
Yan Zhaoge simulated the Great Wilderness Fish-Roc Art with the Peerless Heavenly Scripture, combining forces with the Northern Ocean Clone in manifesting its image.