Tao Sect Supreme: Ten Thousand Ghosts Hidden

With blood as sacrifice to the heavens, he slaughters all evil.

Daoist arts are the strongest.

...

The protagonist, Li Changsheng, cultivates the supreme arts of the Daoist school and makes a great vow: unless he eradicates all demons and evils under heaven, he will never ascend.

He willingly seals away his own cultivation in the world between heaven and earth, lingering in the human realm for thousands of years!