If there's someone who knows well that the presence of mana guarantees the strengthening of one's power, then it should be the one and only celestial fox spirit.
Shen Yuan must admit that although this world has lesser mana and spiritual energy than the spirit realm, it is denser and more abundant than the one he experienced in his previous world.
It is more than enough for him to strengthen his body and powers because he can cultivate and absorb mana at will—a perk of being a fox spirit.
But for humans, this was obviously impossible, given their apparent limitations. They are born to absorb minimal amounts of energy.
And it didn't even help that mana in the atmosphere was too thin for them.
If they only rely on this, then it's impossible for them to become stronger.
