After nearly 250 episodes, and hopefully many more to come, it has always been a dispute between fans as to which episodes were the best. "Supernatural" is made of horror stories, tragedies, and brotherly love; and for this it will always have a fandom, that looks up with adoration (and a pinch of obsession).
5. Lucifer Rising
A poetic/tragic end to Dean's escape from hell, as in this episode Lucifer is set loose from the deepest parts of the realm of Hell.
After Ruby practically ruins Sam and Dean's relationship by tearing them apart, she convinces Sam to kill Lilith in order to prevent the Apocalypse. What no one was expecting was for the angels to want the Apocalypse to happen as well, and for Lilith's death to be the final seal left to be broken. The series ended with one of the most anxiety-inducing cliffhangers in history, with The Prince of Hell stepping foot in the mortal realm.
4. Sacrifice
After Crowley threatened to undo every good deed the Winchesters had ever done (down to the last bit of saved blood), in order to make them stop with the trials, Sam and Dean managed to get a hold of him, in order to cure him and close the gates of Hell for eternity.
Sam became determined not to let Dean down again and took on the weight of the trials to prove himself. They took an extreme toll on his health, and as Sam got sicker, he became ever more defensive of Dean's attempts to mother him. He eventually got to the point where he was so ashamed of letting his brother down that he was willing to commit suicide in order to finish the trials. Dean managed to talk him back from the edge, but they weren't able to cure Sam before he succumbed to the effects.
3. French Mistake
In an effort to protect the brothers, Balthazar sends them to an alternate universe (ours apparently), where hunters do not exist, there is no magic, and where Sam and Dean are characters in a TV Show.
Fans have the best time watching the hunters struggle with normal stuff such as acting, being married to "fake Ruby", and pretending to stab each other with rubber knives.
2.Don't Call Me Shurley
The Darkness, Amara, releases a deadly fog upon a small town, that causes everybody's innermost fears to take over. Amara managed to extract these people's light at the end of the tunnel. Although Sam and Dean tried to handle it, they found themselves locked among the fumes, with Sam on the verge of death (Dean was protected by Amara). In the last moments, as Dean found in Sam's pocket the Samulet which he had dearly saved all those years, Chuck Shirley appeared and undid everything as if nothing had happened; finally revealing the author of "Supernatural" and the universe.
And now for some honorable mentions we include Provenance, All Hell breaks loose, and Bloody Mary. Although they were amazing and breath-taking, "Supernatural" writers crushed the fandom's heart a little bit more with these ones.
1. Swan Song
After deciding to let the fallen Archangel possess him as a vessel, Sam made the ultimate sacrifice to save humankind and protect his brother, thus stopping the Apocalypse. Dean tells Sam that he's there for him and after glancing into the Impala, Sam's memories return long enough for him to briefly take control of his body again. Sam opens the gate to Lucifer's cage, and despite showing apprehension at jumping, he prepares to jump in, but is interrupted by Michael, who asks for Sam to stand back and let him fight Lucifer.
Sam refuses and falls into the cage, where his soul remains trapped for 180 years. This brave little soldier gave up his soul and body when the universe asked him to.
“It’s okay, Dean. It’s going to be okay.”