In the beginning, the world was made of beauty and of magick. Before there were humans, there were gods and those who served them. At war with each other, they fought until a new breed was born out of their senseless violence. Chthonians by name, these new creatures came from the earth that flowed red with the blood of the gods. The Chthonians rose up and divided the world between the gods– they split the world between themselves. To maintain the peace, the soldiers of the gods were ordered to be put down. None were to survive. Chthonian law took precedent and together, they were able to bring peace to the world once more and to protect the new life form of mankind. But the Chthonians were not without corruption. Nor were they infallible. It wasn’t long before they bickered too. And so time moved forward. Mankind matured and learned to dismiss the gods and the magick that existed in their world. Unable to fight on their own, man chose to ignore it. Created by the original gods of light, a Chthonian′s purpose is to keep everything- including the gods- in check. Whenever a god has made an action that can hurt- or potentially kill another god, upsetting the balance of the Universe, a Chthonian is given the charge of exterminating said god. They are bound by different rules from the Greek, or even Atlantean pantheon, and are generally not interested in human affairs. Chthonians are by no means controlled by a god. You get their attention if you′re the Primary Source, or if you can pay a high enough price. Chthonians are part of a deity that is in between. They are neither part of the Greek Pantheon, or the Atlantean pantheon. They generally keep to themselves, and aren′t to be trifled with. At one point the Chthonians had a cival war which resulted in only eight of them left (inculding Acheron). The count has increased to nine from Styxx dying and being reborn into his true powers. To kill one of them you′d have to be a servant of the source or another Chthonian. They are born human. When they first die human, godslayers are reborn and gain their god killing powers. http://darkhunter.wikia.com/wiki/Chthonian_Godkillers

Styxx was born as the prince of Didymos of Atlantis, 9548 B.C. His twin brother Acheron, because of his godlike eyes was sent away, making Styxx forever miss his brother, wanting to lay back to back with him, sneak food and just have the comfort his twin brought him. But as they both grow up in two different environments, Styxx learns his brother hates him with a passion. The hate later turns to Styxx who begins to hate Acheron as well, especially when thanks to Acheron he is sold as a tsulous or sex slave, Acheron attempts to kill him, and his wife and unborn son are killed by Acheron′s real mother. The day that Acheron dies by the hands of the god Apollo and later brought back to life by his mother the goddess Apolloymi, it was found out that Styxx′s life was tied to Acherons. When Acheron dies Styxx dies, but when Acheron is alive and brought back to life, Styxx is also brought back to life. Forever and always, as long as Acheron lives Styxx to will live. When he is brought back to life, Styxx is found by the goddess Artemis, who in a fit of rage, send him to live on a vanishing island, wanting to keep him away from Acheron. For 10,000 years Styxx was left alone to survive and live only with his memories that haunted him. Eventually, Styxx was brought off the island in the year 2004 where he tries to exact revenge on Acheron. After failing, Acheron′s memories where forced upon him by the goddess Artemis. However before she left him in the hands of Acheron, she cursed Styxx, as long as he lived every other week he will have to live as a woman, shifting between man and woman at the beginning of each week. Now stuck with his own tormented memories and his brothers, Styxx lives away from everyone, preferring solitude, until one day his brother comes to him for help to stop the god′s his daughter had unleashed. Not wanting to see the destruction of the planet, even though all he wishes for is his death, Styxx agrees. During the battle against the gods, Styxx is killed this team, this time his death would stay because of the blade used on him. However Styxx was once again brought back to life, but this time because his Chthonian god powers had finally awoken, leaving Styxx a Chthonian godkiller.