Lucifer was created by God billions of years ago, before even the Big Bang, he was raised by Michael and he taught Gabriel various tricks. Lucifer was once the most beautiful and beloved Archangel in all of existence. God loved Lucifer the most of all his angels. Because of his elevated status among the other angels, Lucifer was very proud. When God commanded all those of Heaven to bow down before humanity and to love them more than himself, Lucifer refused, as he considered humans to be a flawed species. Lucifer’s refusal to bow down before humanity was caused by the Mark of Cain influencing his thoughts, as well as jealousy over no longer being God’s favorite creation. Eventually, Lucifer waged a war against God over his decision to create humanity, resulting in God to banish him from Heaven. Naturally, being cast out of Heaven enraged Lucifer, and desperate to prove to God that human beings were indeed a flawed species, he began tempting and twisting the soul of one of the early humans, Lilith. After completely stripping her of her humanity, her soul was transformed into the very first demon. He then would create the four Princes of Hell, some of the most powerful demons nearly impossible to kill, as generals for Hell's army. At some point, Abel began praying to what he believed to be God. In reality, he was actually praying to Lucifer; who claimed his soul for Hell. Desperate to save his brother, Cain bargained a deal with Lucifer by offering his soul instead of Abel’s. Lucifer agreed to the deal; but only if Cain murders Abel himself. Cain does so in order to save his brother and to guarantee he will enter Heaven upon death, becoming the first murderer. Lucifer then bestows the Mark of Cain onto Cain, turning him into the first Knight of Hell, who went on the create more Knights, elite warrior demons nearly impossible to kill, such as Abaddon. Wanting to please his father, Asmodeus attempted to release the Shedim from Hell, creatures so dark, God would not allow them into the light. Fearing the Shedim, Lucifer banished them back into Hell and punished Asmodeus for attempting to release them. God eventually realized that Lucifer’s continued presence on Earth will threaten the existence of his Creation. Instead of killing him, God instead commands Michael to imprison Lucifer in the Cage, a specially designed cell sealed with over 600 seals in the deepest parts of Hell. Michael does so, beginning Lucifer’s long banishment until he faded into legend; with only Azazel being the only demon who did not give up looking for Lucifer. However, it was then predicted that Lucifer will one day, free himself from his imprisonment and begin the Apocalypse where he will destroy humanity, and restore Earth to its original "untainted" glory. It is suggested that Lucifer only uses demons as servants and would eradicate all of them as well, because, despite them being his creations, he considers demons to be even less worthy than humans. Proof of this is shown when he casually kills dozens of them. However, he holds his greatest contempt for Pagan Gods, believing them to be petty, disloyal, and the lowest of all beings because they claim to be gods. Lucifer claims that he never lies or even tricks, because he does not have to, as he has said, "I will never lie to you. I will never trick you." He promised both his vessels, Nick and Sam, that he would be honest with them. He also said that he sympathizes with his vessels, both of whom are victims like himself. He went to some lengths to get Sam's acceptance, sparing Dean's life on several occasions, and allowing Sam revenge against some of the demons that controlled his life. Despite this, Lucifer is largely manipulative and has been proven to mislead on occasion, suggesting that this was more of a ploy to gain trust, rather than an actual commitment, and he would bend this rule when it's to his advantage. Furthermore, Lucifer tries to gain sympathy from his opponents such as Dean by claiming that he is truly a victim and was justified in his actions. Lucifer shows concern for his fellow angels, though it is the archangels he loves most. He captured Castiel and admired the angel's loyalty in refusing to reveal the presence of his friends. He invited his younger brother to join him since they were both enemies of Heaven, but when Castiel refused, Lucifer respected his decision and offered him a chance to change his mind. Lucifer was remorseful when forced to kill what he believed to be Gabriel and was disappointed when Michael berated him. When preparing to fight his older sibling in their pre-destined battle, Lucifer pleaded with Michael to "walk off the chessboard," but Michael remained determined to fulfill his destiny and serve God. Even so, when Castiel struck Michael with holy fire, Lucifer was outraged by the attack on his brother and obliterated Castiel, stating only he had the right to hurt Michael. Gabriel criticized Lucifer, describing his actions as "one great big temper tantrum." Death and Crowley both made similar observations, as they have both called him a bratty and petulant child with daddy issues. Lucifer is also arrogant and extremely vengeful, taking his betrayal and hatred out on the entire world without any remorse. Nonetheless, Lucifer sees himself as a tragic figure who was punished for being right. He refuses to accept any blame for his actions and suggests that God intentionally made Lucifer the way he is, asserting that "God wanted the Devil." Lucifer is also highly cruel and barbaric to those who get in his way, and despite his claims of being the victim, he has no qualms about killing anyone who angers him, even if he has no true reason for killing them. For example, he savagely massacred all the pagan gods (except for Kali, who was rescued and escaped), simply because they plotted against him, despite the fact that they posed no real threat to him and takes great pleasure in beating Dean for being "such a pain in (his) ass." He also slaughtered an entire town by sacrificing the women and children and then having his demons possess the men before killing them just to raise a Horseman. Lucifer has a sense of humor equivalent to Gabriel and Balthazar, rare in many angels. He can be sarcastic and casually indifferent, usually a testament to his arrogance. This highlighted particularly in Sam's hallucinations of him, where he sees him as constantly shedding a snarky and wise-cracking light on Sam's everyday actions. When reunited with Sam in Hell, Lucifer proves to have a comical side, going so far as to dance during a fight with his enemies. While Lucifer is angry with God for imprisoning him, he feels that it's a family issue and that dealing with Amara is more important to the point that he is willing to put aside his differences with his father and the Winchesters to fight her after the torture Amara put him through. After seeing God for the first time in eons, Lucifer initially seemed uncertain on how to react, but soon began to act somewhat like a petulant child, demanding an apology and locking himself in Sam's room when he didn't get one. However, after God actually apologized and explained his behavior, Lucifer forgave him and the two reconciled their differences to the point that Lucifer not only fought for God, he tried to save his father from Amara despite how powerful she was. In the aftermath of the war with Amara, Lucifer seems solely interested in maintaining power in Hell, refusing to let Crowley stand in his way. He displays cruelty towards everyone who slightly upsets him. However, he makes an exception with Rowena, whose powers he is dependent upon until she manages to betray him. Although repeatedly regarded as "evil" by this point, Lucifer was generous enough to keep up his promise with Vince and heal his sister Wendy of her paralysis. Following his banishment by Rowena, Lucifer comes back vengeful against God, believing that God had only apologized to get Lucifer's help against the Darkness before abandoning him a second time. Lucifer is both angry and devastated by this, in near tears when explaining his reasoning to the Winchesters and Castiel. He now sees no point in any of God's creations and intends to do whatever he feels like, specifically stating that he has no other plan. Lucifer's disregard for anyone but himself remains prominent as he seeks out influential humans as his vessels, eventually landing with the President of the United States. Simply for the fun of it, Lucifer takes the president's lover to his bed, and willingly conceives a child with her, the purpose of this is uncertain, though he expresses joy about finally creating something rather than destroying it. He is enraged when Kelly threatens to abort the child and becomes even more furious when Sam expels him from his vessel. As Crowley's prisoner, Lucifer remains confident, humorous and fearless as he does not believe Crowley will get what he wants from him. Even after being tortured, he merely puts up a front that he will submit to Crowley's rule. Although he claimed to have lost his purpose after God's abandonment of him, Lucifer seems to have regained it by focusing on his son. Lucifer also admits to one demon that he is not well-known for his patience. After his escape, Lucifer's primary objective is to be with his son. Alternate Michael, upon reading Lucifer's mind, notes that his greatest fear is being imprisoned again. According to Uriel when recounting Lucifer's rebelliousness in On The Head Of A Pin, Lucifer's true form is apparently considered the most beautiful among angels. However Sam Winchester and Rowena MacLeod had a different reaction to seeing Lucifer's true form, finding it truly terrifying, and remained haunted by it months or even years later, though it is entirely possible that Lucifer’s long imprisonment in Hell warped his once beautiful true form. When manifesting without a vessel on Earth, Lucifer appears as an intense white light, or, when severely weakened, a slender cloud of glowing, bluish-white smoke, identical to other angels. When manifesting within a vessel's mind or in Hell without a vessel, Lucifer usually, but not always, takes the form of his first known vessel, Nick. Nick appears to be Lucifer's favored form to manifest in when Lucifer is in a situation where he gets to choose his appearance similar to how the Alternate Michael continued to use Dean's visage while communicating with a sleeping Rowena. When Lucifer projected his wings while possessing a vessel, they were revealed to have a similar compact design to Castiel's seraph wings and Zachariah's wings, compared to Gabriel and his son's and Alternate Michael's wing designs. Uniquely, Lucifer causes his vessel's irises to glow red and leaves the pupils unchanged, instead of a blue eye-glow with dots of white light in the center. While being an angel, Lucifer appears to have tainted/corrupted grace - according to one angel, Lucifer carries the stench of Hell on him. The prophet Donatello Redfield described Lucifer's power as being dark and toxic when comparing it to his son's. Like Michael, Lucifer required either his true vessel or a vessel from an extremely powerful bloodline to house him permanently - Nick was a notable exception after his body was repaired and modified, enabling Lucifer to possess him for over a year without ill effects. When possessing vessels weaker than this, Lucifer's power would cause the vessel to "burn away" and decay over time, similar to Hael's vessel in I Think I'm Gonna Like It Here, manifesting as burn and rot-like blemishes on the vessel's skin, and in Vince Vincente's case, eventual blackening of the skin and darkening of the eyeballs. While possessing a vessel, Lucifer usually retains the vessel's appearance without altering it.