Ever watch a vampire China? Ghosts are usually portrayed as the undead can move and suck human blood. Anyone who sucked their blood will also be turned into a vampire.
In Chinese folk tale or legend, a vampire known as Jiangshi or also spelled chiang-shih. Jiangshi usually described as rigid bodies dressed in official of the Qing Dynasty and moves by jumping and stretching out his hands to the front.
Jiangshi be killing living creatures to absorb qi or "life energy" which in this case in the form of blood. Ghosts are usually out at night, while during the day he would be lying in a coffin or hides in dark places like caves.
Ji Xiaolan, a scholar of the Qing Dynasty, had mentioned in his book Seeds Yuewei Caotang that the cause of the undead can be classified into two categories, namely those who have just died and came back to life, or the bodies that had been buried for a long time but did not rot.
Here are some of the causes that triggered the dead back to life as described in his book, Ji Xiaolan, as reported by Wikipedia.
1. The chemical composition of the burial ground is not suitable for living organisms, so that the bacteria did not appear to help in the process of decay. Hair and nails are the bodies appeared to be growing and there are no real signs of decomposition. If left untreated, the body will eventually become Jiangshi from time to time.
2. The use of occult sciences to revive the dead.
3. There is a spirit which enters the bodies.
4. Bodies were successfully absorb the qi enough to return alive.
5. The person who died was not immediately buried even after the funeral has been held. Corpse to life after being struck by lightning, or while pregnant cat (or a black cat in a few stories) jumps on the coffin.
6. When a person's soul fails to leave the dead body due to improper death, such as suicide, or just want to cause trouble.
7. A victim of premature burial.
8. A man who was injured after being bitten by a vampire, so he was infected with "the virus Jiangshi" and gradually transformed into Jiangshi.
If viewed from a ghost, it seems Jiangshi and pocong be best friends because they have quite a lot of similarities. The difference is, the clothes of the Jiangshi more luxurious and more freely move their hands. Just kidding!