"How art thou fallen from heaven, O Lucifer, son of the morning! How art thou cut down to the ground, which didst weaken the nations!" -Isaiah 14:12
The Light Bringer certainly remains one of the largest enigmas in reality, much less the setting of Kult... this article is not intended to be a thesis on the creature known as Lucifer and should not be implied as such.
In Kult, even God is against us and we have very little hope of ever achieving salvation. Everything we believe is not just a lie, but also a perversion of the truth, and if this is true, what of the fallen ones? The one-third of Heaven's Host that was cast out? Please note that this isn't to be confused with canon material... this series of articles is only based upon how I run my games. Feel free to use and modify this as you see fit for your own games.
Who is Lucifer?
Lucifer, the Morning Star, Father of Lies and Prince of Darkness are the titles we are so used to, that they have become ingrained in our minds. Oft identified as Satan and falsely represented as Astaroth, Lucifer is neither of these. Lucifer is Logoi, one of many Self-Born. He existed before his own creation as an example, a form of perfection even amongst the Host. Lucifer suffered from the sin of Pride and was cast from "heaven" for his sins and his rebellion.
The Demiurge created Lucifer and the others of the Host using no more than mere spirit forms or archetypes that had already existed. He formed these archetypes into his Angels, his ministers... his slaves. The Demiurge trapped the Angels in a similar manner to the manner in which he trapped mankind... by imprisoning them into a form of matter. This creation of the Angels in this manner was for two very simple reasons... power and control. Having both man and angel trapped in matter gave the Demiurge control over them.
After the Demiurge decided to imprison mankind, the Angels were used as Slaves for the Demiurge to create his Lie from the body of Malkuth... and afterwards to administer his justice and vengeance. The angels were sent forth en masse to create what the Demiurge willed, A Prison. Lucifer, the Foremost and most powerful of these Angels refused, and of course a vast number of those under him agreed, and also refused. Refused to obey the will of the Demiurge, refused to create his prison over mankind.
It's important to note that this rebellion was not out of any love for or sense of duty to mankind, but rather a form of protest and simple fear... Protest at other emanations of the Logos or Will being treated in such a manner. After all, if the Demiurge can imprison mankind, what is to stop him from imprisoning the Angels as well? Without mankind, the Demiurge no longer had anything to stop him. Fear played its part as well, the fear of the firstborn, the Angels, being replaced. Lucifer hated mankind for that, for being more beloved to the Demiurge than his first creation was. Of course in the end, none of that seemed to matter any longer. Lucifer in a single act of defiance had freed himself from his bondage to the Demiurge. Lucifer had awakened from his slavery and regained his free will. He realized that by serving the Demiurge, the other angels had given their own free will away to serve the Demiurge's creation, becoming nothing more than automatons. And so he told them that they did have a choice, that they did not have to serve the Demiurge.
Lucifer, for his rebellion, was cast from paradise into "hell". As we all know, hell is a subjective matter. In this case "hell" is merely another word for the Illusion. The commonly believed myth of Lucifer stems from misinformation and deceit. This is what The Demiurge wants. It is the gestalt of the legend of his fall from heaven and the myth of Astaroth. Throughout our history mankind has perverted even the Lie. Lucifer's hell is merely our Illusion.
This doesn't mean that Lucifer does not have his own private purgatory - in fact he does. It is populated by himself and his fellow rebels of heaven. The main differences between his realm and our personal hells are many, however. The most important of which is that Lucifer may at any time escape his, and with his permission so can many of the others. It is important to note that he works through Avatars rather than appearing directly, much like the Archons. The second most important difference is the lack of torturers. Lucifer laid them to waste long ago. Those that do still survive there are nothing more than whimpering yes-men and servants.
Lucifer and Mankind
Lucifer's relationship with man is ever an old one; one tainted my centuries of lies and myth. Lucifer does indeed hate mankind on a level unequaled by any, but not as much as he feels betrayed by the Demiurge. One of the first things Lucifer did after mankind was imprisoned was teach them about good and evil, and tell them of their true origins. This plan almost worked and indeed did for a short time. However, the Demiurge was clever enough to convince mankind of Lucifer's "Evil Nature" and he was discredited. The final blow was the fall of the Tower of Babel and the "Scattering of Tongues." A common tongue had until that point, united mankind. This alone plunged humanity back into ignorance. Lucifer intends to use Mankind to destroy the Illusion in which he is trapped as well. Thus far, Lucifer's plan is working.
Malkuth knows of Lucifer's plan and is secretly helping by sowing seeds of mistrust in organized religion. For the time being, Lucifer is helping mankind to realize its true natures, but it's only a matter of time until he turns on us as well.
And with the Demiurge gone, there is little to stop him.