I Wish to Cultivate the Demonic Path

Any Stories with a Demon Cultivator or Evil Cultivator Protagonist?

An Invincible Protagonist Who Cultivates Demonic Arts

As long as it's about an invincible demonic cultivator, anything goes.

Cultivating Evil and Demonic Arts, Practicing Only Unorthodox Techniques

Looking for books similar to Reborn as a Demonic Cultivator, Picking Up a Zombie Planet from the Start.

The Male Lead Joins a Demonic Sect and Cultivates Its Techniques

The protagonist is the current leader of a demonic sect, secretly correcting orthodox cultivation techniques every day, and the sect's bigwigs still haven't noticed! Are you that good at hiding it, or are all the bigwigs undercover agents? I don't need the protagonist to kill people to cultivate. I just want the male lead to practice the sect's own demonic techniques. No stories where he takes in a few people and every single one turns out to be a prodigy.

The MC Should Practice Demonic or Evil Cultivation and Blood Magic, in a World Like A Record of a Mortal's Journey to Immortality

For example, something like The Immortal Journey Through a Sea of Blood.