The Necromancer Saint

Yujin Cheon, the first-ever hunter to achieve 9-star rank without the help of a constellation’s blessing, holds incredible power with his undead army. But this very power makes him a target of the 7 Great Houses, and he’s forced to use an artifact to go back in time or else die. He wakes up 23 years in the past, ready to become a constellation’s saint, regain his power, and exact his revenge.

Source: Webtoon