I noticed that too. Why would they call a Wraith a "Plesen"? I've already given examples of the carelessness of the localizers.
Added 3 minutes later
I translated it from Macmillan, and that dictionary is one of the best in the world, and it says that both "Spectrum" and "Ghost" translate to "приведение" in Russian.
So, let's summarize. Six units are known: sphinx, skeleton, spider, ghoul, vampire, wraith. Let's bet on the seventh :).
Цикл "Закадычные враги": "Особенное гостеприимство, "Супероружие", "Меж молотом и наковальней"
"Падение Шантири"
Кампания для "Кодекса Войны"
"Выбор Сагиттеля"