>>149777278
>The entire concept of ghosts and the undead is stupid and doesn't make any sense.

Well, it's too easy to understand and separate into different branches:

Zombies/skeletons fall under the Undead, or in the case of Zombies, they have a subclass for zombies resulting from the infected.

Ghosts are ethereal forms and the soul of a living being. Although they emerge after the death of said being, they shouldn't be considered Undead because they are like a semi-transcended form of the being to a higher plane.