Becoming evil makes you ten times stronger, but becoming a demon gives you hundredfold strength

Meng Yu's Golden Finger was called "Corruption Strengthens Tenfold, Becoming a Demon Strengthens Hundredfold," both extremely fierce and convenient to use. "Those who consume Qi are divine and long-lived, constructing the foundation of ten-thousand generations, and on the day they achieve immortality ('Dan'), they break the self of yesteryears ('Infant'), transforming into heaven and earth, thus becoming immortals." This is the eternally correct tale of the Qi Refinement Practitioner Meng Yu's grand cultivation adventure. — Description from novelcodex.org