Achieving physical sainthood starting from Hunyuan Gong

In this world, there are humans, demons, and gods. There are emperors who overlook all living beings, powerful sects that wield absolute authority, wealthy and powerful families who dominate the masses, and brave warriors who roam the world alone with their swords. Song Shen, transmigrated to another world as a slave, initially only aimed to survive, able to only look up to those unattainable beings. Things changed when he awakened the "Eternal Proof" panel and the infinitely useful Dao Fruit ability. Once that experience bar was full, he could slay immortals, Buddhas, gods, and demons with a single strike.