Starfinder: Desiccated
Say what you will about the merging of Necromancy and technology, they have created some of the most terrifying undead monsters ever to walk the prime material plane. During the search to create a viable zombie-like weapon of mass destruction, many different viruses were created and tested on the unsuspecting.
One partial success that they stumbled upon was creating a virus that reanimated the dead, but instead of turning them into mindless creatures that hungered for the flesh of the living, they created semi-intelligent monsters that instead of craving flesh, required blood.
These particular undead monsters have the appearance of a zombie, but are in fact vampires. They decay to a point, typically accumulating about three to four days’ worth of decomposition before it halts for good. The wounds that killed these creatures never actually heal, and clearly set them apart from the living. Most of the time the wounds are located on the neck or throat of the victim, as that is where the creature always tries to attack in order to gain the blood it requires for survival.
If the undead state it is in could be considered to be a form of survival.
Many who encounter these creatures believe that they are simple zombies and as such are easily dispatched, but they quickly learn that they are anything but. In order to lure victims into dropping their guard or becoming overconfident, they will shamble around and act mindless. But they are in fact quite cunning even if they no longer possess the same level of intellect that they had before succumbing to the virus that created them.
The only way to really kill one of the creatures is to destroy the brain, much in the same manner as destroying a zombie, or simply to inflict enough damage to destroy the body. Fire and acid are a great way to destroy these creatures. They cannot heal damage from either except by feeding. Furthermore, cold is another excellent way of dealing with these creatures.
Also they are still capable of using armor, weapons and equipment, and often will do so, and are especially prone to using armor, despite their ability to regenerate damage they have sustained.