Spoilers ahead for the Supernatural: The Long Road Home special presentation on The CW.
The long road to the end of Supernatural has come to an end, but not without a special presentation that revisited the highs and lows of the saga, including one of the most iconic scenes of the whole series: Castiel's epic entrance. Back before Cas went ahead and raised Dean from Perdition, Dean didn't even believe that there was such a thing as angels. Then, he and Bobby summoned whoever dragged Dean up from Hell, and Castiel arrived to change the entire show forever. Misha Collins recalled his reaction to Cas' entrance in the Season 4 premiere, and it's pretty funny in hindsight.
In the Long Road Home retrospective, Misha Collins took fans back to his thought process upon Castiel's arrival:
As I’m walking through the barn doors, the overhead lamps are exploding because I’m such a powerful character. Bobby and Dean are firing shotguns at me, I get stabbed, and I thought, ‘God, if this is what it’s gonna be like on this show, I don’t know how much of it I can take.’
It's almost hard to remember a time on Supernatural when Castiel wasn't a key part of the story, and Misha Collins has certainly been the third lead of the series after Jared Padalecki and Jensen Ackles. Cas may have died and come back more than any other major character with the exception of Dean, who racked up quite a death count back in Season 3. Blood, sweat, and tears have been shed for and by Cas.
So, in the grand scheme of things, I think it's pretty funny that Misha Collins wasn't sure how much he could take based off of his character's entrance all those years ago. If only he knew then all that was going to happen with Cas over the 11 seasons to come! Between the bonkers plot twists, Castiel's many deaths, the meta outings, and the behind-the-scenes shenanigans among the cast, things were only going to get crazier.
Of course, the Castiel who got the iconic entrance was a far cry from the angel who would fall from Heaven and ultimately give himself up to the Empty out of love for Dean and humanity. Misha Collins went on in the Long Road Home special to comment on how far Cas came over his 11 seasons on Supernatural:
Seeing him grow to find love and acceptance within the human family has been gratifying over the years. It’s a show that’s at it’s core about family relations and love, and that’s something that all of us can relate to.
While fans will likely debate forever what exactly Cas meant in his confession of love to Dean before giving himself up to The Empty, the penultimate episode revealing "Castiel" carved into the wood table in the bunker along with Sam, Dean, and Mary's initials (and Jack's name) says everything about what Cas meant to the Winchesters and the show.
In case you need a refresher on Castiel's game-changing entrance and a reminder of how far he came before he ultimately sacrificed himself at the end of Season 15, check out Misha Collins' Supernatural debut in the Season 4 premiere:
Thanks to Castiel's big speech before sacrificing himself to The Empty, I think it's fair to say that this was an example of love at first stab! Even other angels have said that Cas was lost as soon as he laid a hand on Dean to raise him from Hell and became part of the Winchester saga, and Sam and Dean's journey would have ended a lot sooner if Cas hadn't fallen.