Dean and Lucifer

Dean Winchester and the archangel Lucifer are primarily mortal enemies who try to kill each other every chance they get.

Season 3
Dean first learned of Lucifer being real from the demon Casey while they were trapped together. Dean was surprised to learn that Lucifer was real, having previously thought him to be a fairytale.

Season 4
After learning that Lilith is breaking the 66 Seals to free Lucifer from Hell, Dean dedicates himself to preventing his rise. The angels claim that Dean will ultimately be the one to stop Lucifer, but he eventually learns from Zachariah that they want to let Lucifer rise so that they can beat him and have paradise on Earth. Dean attempts to stop Sam from killing Lilith and releasing Lucifer with Castiel's help, but ultimately fails due to the intervention of Ruby.

Season 5
With Lucifer on the loose, Dean dedicated himself to finding a way to kill the archangel. After learning of the Michael Sword, Dean believed that if he could find and use it, he could kill Lucifer only to learn that he was the Michael Sword: the one true vessel of the archangel Michael whom he would possess to have his final battle with Lucifer. Dean subsequently spent months fending off efforts by the angels to get him to say "yes" to Michael so that Michael could use Dean's body to kill Lucifer, a fight which would destroy half the planet.

Dean met Lucifer for the first time when Zachariah transported him to an alternate future in the year 2014. This Lucifer possessed Sam which horrified Dean as Lucifer was shocked to see him but casually greeted him. He chose to spare Dean, right after killing Dean's future counterpart. Lucifer attempted to get Dean to understand him, but Dean bit back saying that he was like every other monster Dean hunted, the only difference being the size of his ego. Breaking into tears at failing his brother, Dean told Lucifer to kill him or he'll find a way to kill him as the latter remarked he liked Dean and ended their conversation with assuring Dean that they would "always end up here". This trip also caused Dean to make amends with his brother and they started hunting together again.

In the present, Dean sought to kill Lucifer by using the Colt, though the plan failed and Dean was left with relying on Sam's own plan of saying "yes" to Lucifer in order to send Lucifer back to his Cage. Dean watched as Lucifer abandoned his previous vessel for Sam, and then took Sam for his own. After gloating briefly to Dean, Lucifer departed without bothering to kill him.

At Stull Cemetery, Dean interrupted Lucifer's battle with Michael and glared at him after he insulted him before stating he wanted to speak with Sam. After Castiel sent Michael away, Lucifer killed Castiel and Bobby as he proceeded to beat Dean up, calling him "a pain in my ass." Dean called out to Sam as he was attacked and Sam eventually managed to take control of his body, and return Lucifer to his prison at the sacrifice of himself. Shortly afterwards, Castiel was resurrected by God and he was able to heal Dean's injuries and bring Bobby back.

Season 11
Dean did not meet Lucifer again until about five years later, when Sam convinced him to allow him to speak to Lucifer. Unfortunately, Lucifer had set up a plan to escape the Cage, and despite Dean's efforts to stop him, Lucifer got out. Dean would not known of this for a time, and conversed with Castiel, unaware that Lucifer was possessing said friend. When Dean did find out, he made an effort to rescue Castiel.

Lucifer repeatedly mocked Dean over his concern for Castiel. Originally, he planned on using Dean's connection to Amara for good use, but after discovering, and subsequently obtaining a Hand of God thanks to the brothers, he ultimately chose to be rid of Dean and Sam. His effort to kill the brothers failed when Amara herself kidnapped him, an incident which he blamed the brothers for. Later on, Dean arranged a rescue mission to retrieve Lucifer, believing him to be a necessity in the war against Amara.

Once the archangel was at the Bunker, however, Lucifer began throwing a teenage tantrum at his father, forcing Dean (and Sam) to get the two to sit down and talk. Afterwards, Dean and Lucifer worked together to fight Amara, though they continued to annoy each other. Amara eventually expelled Lucifer from Castiel's vessel, much to Dean's delight, as it returned Castiel to him. However, Dean was shown to still worry about Lucifer enough to check on him when he thought Lucifer was still inside Castiel, and asked what happened to him after his eviction.

Season 12
After God and Amara's reconciliation and departure, as well as after the confrontation with Toni Bevell, Dean learned from Castiel that Lucifer was still out and about and Castiel planned to capture him, something Dean offered to help with. Eventually, Castiel accepted his help and Dean traveled to Los Angeles to interrupt a concert Lucifer was hosting. Dean succeeded in chasing the guests out with gun shots fired at the ceiling. Lucifer was obviously unhappy about this, and he and Dean, Sam and Castiel got into a brief struggle, in which Dean handcuffed Lucifer.

Lucifer greeted him with mild surprise and threw him off the stage and melted the handcuffs from his wrist. Dean then bore witness to Lucifer's confession and why he was motivated to kill people randomly. Dean showed no remorse over Lucifer's sense of betrayal caused by his father's abandonment, and merely looked on in dislike as Lucifer vowed to destroy the humans in retaliation. Dean taunted Lucifer about the deterioration of his vessel, to which Lucifer agreed that Vince Vincente was wearing thin, and promptly left the vessel. Dean vowed to capture him.

Dean and Sam followed Lucifer to a church and then towards the President of the United States, who was Lucifer's next choice for a vessel. When Castiel sensed the conception of Lucifer's child, Dean remarked how he didn't know the archangel was dating. Dean later accepted help from Arthur Ketch and used his equipment to free the President from possession and send Lucifer back to Hell. Both and Sam expressed joy at finally defeating Lucifer.

Months later, Dean finds out that Lucifer had not been returned to the Cage due to Crowley's personal intervention, which has allowed Lucifer to escape a much weaker confinement. Dean angrily confronts Crowley about this, but agrees to work with Crowley again in defeating Lucifer, who is now in search of his unborn son. Dean, Sam and Castiel confront Lucifer outside Kelly's cabin, and plan to lure him and trap him inside a portal opened up by Lucifer's son. Once Lucifer is inside, Dean acts as a distraction by firing numerous bullets into Lucifer while Sam and Crowley finish the spell to close the portal.

Lucifer is unharmed, and while the spell gets completed, Lucifer is still able to escape the portal and kill Castiel right before Dean's eyes. Dean then witnesses his mother and Lucifer fall back into the portal during a scuffle between the two. The portal closes behind them, leaving Dean with a dead Castiel.

Season 13
Dean is quick to convince himself that Lucifer has murdered his mother and initially treats Jack with disdain since he is Lucifer's son. He assists both Sam and the resurrected Castiel in convincing Jack to choose them over his father which they succeed. He also learns from Jack that Lucifer has not killed Mary though unaware that Lucifer himself has returned.

In Devil's Bargain, Dean was shocked to hear from Castiel that an Alternate Kevin used a spell that allowed Lucifer to return. When confronting Lucifer, Dean was angry to see him again and made it clear that he will kill the latter in time but needed to get Jack and Mary away from the alternate Michael who wants to invade their world. However, Anael aided Lucifer who began torturing Dean, Sam and Castiel but Arthur Ketch intervened and Lucifer retreated.

The two met again in Beat the Devil, after Gabriel and Rowena MacLeod captured him and brought him back. Dean was pleased to see him in a weak state and nodded in agreement with Sam to killing Lucifer after rescuing their mother.

During Exodus, Dean was angry to see Lucifer again even more so as the latter approached Jack. He was determined to make sure they stayed separated by telling Gabriel to kill him as Lucifer remarked they needed him against Michael. Reluctantly, Dean allowed Lucifer to join the group and they worked in evacuating the apocalypse world survivors to Earth. Dean also watched in horror as Lucifer was defeated by the Alternate Michael. Dean referred to Lucifer being trapped as "Sam handling it".

In Let the Good Times Roll, Dean was worried when both Lucifer and Michael returned to the Main Universe and that the latter had Jack. After Lucifer becomes super-charged by stealing Jack's grace and has taken Jack and Sam, Dean becomes willing to make a deal with the alternate Michael to defeat Lucifer. Acting as Michael's vessel and powered by Michael, Dean was able to finally kill Lucifer and end his reign of terror. Dean was pleased that he was able to kill Lucifer, though he felt that they did it as a family and seemed stunned afterwards that he'd managed to accomplish the feat.