Manga Like Wangling Fashi: Cong Kulou Fenshen Kaishi Cheng Shen

The main character awakens the useless class "Necromancer" — but gains a skeleton clone in the underworld. Using this skeleton clone to kill monsters and level up in the underworld, he feeds the power back to his main body, continuously growing stronger. This is not limited to satisfying the feeling of pleasant growth for a character who depends on cultivation, but also takes advantage of information asymmetry to repeatedly create opportunities for "playing the fool to crush the strong." From a single skeleton, he embarks on the road to godhood.