Undead creatures are beings that even though are definitely deceased demonstrate some aspects of still being among the living.
This grouping will include ghosts, spirits and corporeal beings such as vampires and zombies. Ghosts, spirits and apparitions can spook and terrify us into believing we are losing our minds. Vampires and zombies can physically attack us and sometimes transform us into one of them.
It would seem very common in tales that most ghosts and spirits become a hassle or threat to the living only when they seek closure. This usually involves an evil deed that was once carried out against them while they were still among the living.
Since they are essentially sentenced to exist in limbo while forever waiting, being tortured and taunted with the lack of resolve and/or vengeance, a means to an end is the only thing they desire and seek.
Others are just evil to the core for absolutely no reason – perhaps puppets or mere soldiers at the mercy and command of a much greater evil.
Physically enabled beings such as vampires and zombies have terrorized and forced us to try and overtime prove some very effective techniques to help the living guard against them.
Depending on which story you read though, it is very difficult to feel 100% confident that any of these methods would actually work. That is probably why in many accounts, the preyed upon often try to use many if not all defense methods. Victims try everything hoping that something will finally do the trick.
Undead Creatures A-Z List
Drekavac – Also known as Drek or Drekalo, this undead mythical creature comes from the souls of unbaptised children.
It is described in various ways but mostly as having the body of a dog or fox with large hind legs like that of a kangaroo. This creature is known for its screams. It will even sometimes appear near cemeteries in the form of a child crying to be baptized.
The Drekavac can be seen at night, lurking in caves and tunnels. In the form of a child – it means imminent death. In the form of a canine – it is an omen for cattle disease.
Similar to the Banshee, the cries of this mythical creature predict death.
Source: Slavic Folklore
Varcolac – Undead wolf demon. The Varcolac or Vircolac is a wolf-like spirit creature that can grow large enough in size to be able to swallow the moon and cause eclipses.
It emerges from the corpses of babies – the deceased offspring of unwed parents or unbaptized children.
Source: Eastern Europe