The death of Kevin Tran was a tragic one in Supernatural Season 9 Episode 9. "Holy Terror" was a major turning point for the season that saw Gadreel as a hit man, angel on angel warfare, and Dean's heartbreaking last moments in the hour that would ultimately spur him on to save Sam and defeat Metatron.

Supernatural Season 6 Episode 15 went full on meta with the "French Mistake." This was a hilarious and exaggerated look at the cast and crew of Supernatural that's full of humor and in-jokes. This one's for the fans.

Supernatural Season 3 Episode 13, "Jus in Bello," was the demon assault on the sheriff's office to get at Sam and Dean. It was an intense and action-packed hour that included Agent Henrikson's last stand, seeing Lilith go full white-eyes and Dean trying to impart some comedy with a well timed Bob Marley lyric.

Supernatural Season 2 Episode 12, "Nightshifter," was an episode that introduced a scary and clever monster that was the shapeshifter and the start of the FBI hunt after the brothers. Plus, who doesn't love the bad ass end escape sequence set to "Renegade" by Styx?

I know, the Leviathan season. But Supernatural Season 7 Episode 1, "Meet the New Boss," began with such a frightening presence in Castiel going from God to Leviathan that I was excited to see what came next. And then came next.

Supernatural Season 5 Episode 22 was show creator Eric Kripke's fantastic exit in "Swan Song." The history of Sam and Dean was on full display. Dean took a beating to try and stop his brother and the apocalypse. Sam sacrificed himself. And a saga closed one door before cracking open the next phase of the Winchester journey.

Supernatural Season 8 Episode 23, "Sacrifice," was an emotional and tense filled hour. Some great performances all around, especially in the final scenes with Sam and Crowley, and a visual spectacle of the angels falling from Heaven was the icing on the cake.

Dean is back from the dead and the introduction of fan favorite and now series regular, Castiel? Supernatural Season 4 Episode 1, "Lazarus Rising," was an exciting kick-off that introduced the angels and the epic reveal of Castiel's angel wings in the barn. The mythology was just beginning to ramp up the angel/demon storyline. And wow, was it an awesome direction for the series.

What? Another Season 5 choice? I can't help it, but Supernatural Season 5 Episode 8, "Changing Channels," is one of my all time favorites. The humor, the clever use of television shows such as Grey's Anatomy and CSI, even herpes commercials, in addition to revealing that the trickster is actually Gabriel? This hit so many marks for a great episode that it was as much standalone as it was part of the bigger mythology.

It's tough to not pick the pilot, Supernatural Season 1 Episode 1, because it introduced us to Sam and Dean in the first place. Combining the creepy scares, the spot on humor and the mysteries of their mother and Jessica’s death, all while pushing them to find their missing father was a great way to get their (and fans') Supernatural journey started.