WARNING: The following contains major spoilers for The 100 Season 7, Episode 16, "The Last War," which aired Wednesday on The CW.

After seven seasons, The CW's popular post-apocalyptic series The 100 has finally come to an end, as the fate of the human race is judged by a mysterious higher power. In the end, after initially found to be lacking, humanity was deemed worthy and transcended its physical form to evolve into something greater. However, series protagonist Clarke Griffin was not among those who ascended, left behind on Earth only to be reunited with the friends who chose to stay behind with her.

In an exclusive interview with CBR, series creator and showrunner Jason Rothenberg discussed the creative decisions behind the series finale, explained why Clarke wasn't ultimately allowed to transcend despite all she had sacrificed over the course of the series and shared the overall message behind the long-running show.

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This has been building for awhile. Clarke has had to shoulder the burdens of the entire human race throughout the series, especially the last couple seasons. How was it developing the payoff to that and working with Eliza to realize it on the screen?

Jason Rothenberg: Weirdly, Clarke's arc and Murphy's arc are almost opposite each other. We start Clarke in a place of pure heroism, almost too good, and obviously she ends in a place where she's the last human being on Earth because she was not allowed to transcend because of all that she's done. To me, that was always a fascinating challenge... she's not a villain, of course, she's our protagonist, but she's not a hero. She's a broken, flawed character who, ultimately, was doing awful things early on and we were cheering for her because she was doing it to people we didn't care about or were rooting against; Mount Weather, for instance, even though there were innocents there -- and [we're] kind of putting the audience in the role of Mount Weather by Season 7.

We now know what it's like to be on the other end of Wanheda's gun because she was killing people who we care about. And I think there was something delicious and subversive about that -- and the audience has to be judge, of course -- but it was not your typical arc for the protagonist of a show, for sure.

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Were the characters encountered inside the Anomaly Stone for the test always going to be Lexa, Abby and Callie?

Rothenberg: There was definitely a lot of discussions about who the judges should be, but once we kind of landed on what the rules were -- which is that it's either your greatest love, your greatest teacher or your greatest enemy -- then it started to become clear as to who those judges would be. And once we landed on who the three characters that were going to be facing the judges were going to be, it became an exercise of can we get certain people, like Alycia Debnam-Carey for example, to do the episode. That took some conversation, for sure, and thankfully she agreed to do it. Same with Paige Turco. Paige was not on the show anymore and she was so game and open to coming back, and it was so amazing to have her.

Although Iola Evans, who plays Callie, and will hopefully continue to play Callie, wasn't with us very long, it was pretty great working with her on the prequel. So to get the opportunity to direct her, even though it was only in those one or two moments, was great for me. She is such a special talent.

Clarke makes sense and Cadogan makes sense but what made Raven the right character to take the test as well from all the other characters?

Rothenberg: Raven has always been the backseat hero who saves the day and, on some level, the purest hero that we have, although obviously, this season we put her in some situations that gave her a taste of what Clarke had been through. Ultimately, having Clarke go in and boldly fail the test because of her act of vengeance and then having Raven come in and appeal the verdict just made sense to me.

As an aside, stellar choice with that U2 song at the end. That's my favorite song off of The Unforgettable Fire.

Rothenberg: [Laughs] I love that song! That's my favorite song of all time, which is why it's in the show. It's not particularly relevant although I could make an argument for it knowing what the song is about and where the lyrics land. But I'm glad you like it; to me, it's the greatest non-Springsteen song in the history of rock'n'roll.

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What are you hoping the fan base takes away from this story? You land on, I think, as happy an ending as you can get, but there is an element of it being very bittersweet too with the terms they end with.

Rothenberg: Yeah, I feel like bittersweet is what I was aiming for, for sure. Ultimately, the ending of a show and experience that you love is bittersweet, emotionally speaking. So the idea that [the] narrative kind of captures that emotion is good and appropriate, and again, what we were aiming for.

Ultimately, as I've said before, the way a story ends is kind of the moral of the story; what that story means. And I wanted to not have the show kind of say, "Yes, tribalism is bad and we're all going to kill each other and that's the end." I wanted there to be what's on the other side of that equation. If we don't get over our tribalism and we don't realize we're all in this together, then we're doomed. If we do realize it, put our weapons down and link arms and realize that this is all one crew that we live on this planet with, then we have a chance to evolve to whatever that next level of humanity is.

And the bittersweetness of it is that Clarke isn't allowed to transcend; Moses doesn't go into the Promised Land at the end of the story. And, in this case, she's not alone because her friends -- knowing what she sacrificed for them and how many times she sacrificed herself for them -- chose to stay with her because they love her. And there's something obviously hopeful about that.

The 100 stars Eliza Taylor, Marie Avgeropoulos, Bob Morley, Lindsey Morgan, Richard Harmon, Tasya Teles, Shannon Kook and J.R. Bourne. The series finale is available to stream on The CW's app and website.

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