Discussion of the Necropolis faction.

Ghouls are European undead, with Arabian malevolent jinn ghouls as their prototype (in Russian, they are written the same, but in English, the spelling of the words differs; first, they are translated as "Ghouls" and "Vampires," and the latter are still called Ghouls).

As far as I know, there are no mentions of ghouls in the Russian language at all, since ghouls are translated from English as vampires, or as you already said, as ghouls. There is another spelling in English, but it is translated as a corpse-eater.

Added 22 minutes later

In the end, there are three options for translators (off the top of my head) for these creatures:
1. Ghost
2. Specter
3. Spirit

"Ghost" is translated as "specter" in English, and I also forgot about spirits. It would be good if ghosts and specters were incorporeal, as in Heroes of Might and Magic V.