Yes and no. Considering how much work death witches do with the spirits of a dead, a general belief in the afterlife is necessary. However, I do know some death witches who engage in past life work as an aspect of their craft instead of working with ghosts. Death witchcraft has the flexibility of neatly fitting into most religious beliefs.
Is death witchcraft a “dark” path?:
If you mean “dark” in terms of “evil” or “negative,” then no. Of course death witchcraft involves death, an idea that many people feel uncomfortable with. And it can be a hard and draining path. But evil? Or unethical? Not at all. With death witchcraft, you have the opportunity to heal yourself and souls around you.