Meht

The Meht is a widely-feared species. Members of it can be found on multiple planets and the species has spread to other galaxies.

Background
The Meht is commonly known as a widely-feared species created via a genetically engineered disease. This disease is transferred via a single bite performed by a host on a victim. The more bites the infected host performs, the more the infection spreads to the victim. When the victim is completely infected, they take on a menacing and demonic form; their hair grows long, their eyes begin glowing red (or green, depending on the host), their hands and feet reshape to have claws on their 4 fingers and toes, they take on a bony form, and their skin turns jet-black to dark grey. Those who are infected by this disease will gain the ability to spread this infection via biting others. They are most common in the Coruscant Underworld where the poorest people live. Due to the large amount of Meht activity there, the Galactic Republic was forced to start an operation to protect the people in the Coruscant Underworld, setting up gates that kept the Meht from reaching the potential victims or any way up to the higher levels of Coruscant.

Origin
The original Meht (and the ones that spread the disease)were an advanced civilization in a far away galaxy. Unfortunately, they soon used up all their resources over the centuries, and in time the species started to die out. Unable to continue faster-than-light space travel (and thus keeping the species from traveling to other galaxies), the scientists desperately started to perform genetic experiments on various members of their species in an attempt to save it. Only a few projects succeeded; those projects were given special capabilities, allowing them to slowly mutate members of other species into a similar-looking being via biting, very much like the Rakghouls. Additionally, these experiments, over the course of years, were able to be given the ability to regenerate their body parts (and thus able to spread the infection more effectively). These successful projects, species' last hope, were placed in individual pods and launched out into space while the the species began to die out. While these experiments floated off into space, the rest of the Meht, hoping to find another way to save their species, began mining the remaining planets in their galaxy, hoping to gain enough resources to travel to other galaxies themselves. Most of the experiments were destroyed during their journeys due to hazards in space (being caught in a star's gravitational pull, a black hole, or astroids), but by around 6,000 BBY, the few that survived entered various galaxies, such as "the galaxy", Rishi Maze, the Yuuzhan Vong galaxy, and even the Milky Way. Upon crashing on a planet, the experiments were freed from their pods, and immediately began the mission they were assigned by the original Meht: infect other humanoid species and spread the species to other galaxies. Those experiments have a prolonged life, and exist even to this day.

The infection
Those who are infected will slowly mutate, eventually taking on the appearance of a Meht. The host will keep the memories of loved ones, locations, and security codes, thus making it more effective for them to locate and kill or infect victims.

Details:
 * Any humanoid species is susceptible to infection.
 * Corpses can be infected, though they will be more clumsy and have less intelligence than a regular Meht.
 * If the corpse was infected prior to death, the infection will cancel out and the body will become immune to infection.
 * Additionally, the infection requires the nervous system of the victim, so any body without a head or brain will be immune to infection.
 * Large species cannot be infected.
 * The amount of times a victim is bitten determines the rate of infection; it can range from mere seconds to minutes or even hours or days.
 * There is an antidote, but it must be applied immediately due to the fact that over time, it will have infected the victim too much, and thus it would be too late to remove the infection.

Trivia

 * I got the idea for the Meht after my encounter with the Rakghouls in Knights of the Old Republic.
 * The Meht were originally called "Them" due to nobody in the Star Wars universe knowing the background of the species, but I decided to give them an actual name in time.
 * Several models of the Meht have been made. They will be uploaded soon.