WARNING: The following contains majors spoilers for "Fadeout," the series finale of Arrow, which aired Tuesday on The CW.

The Arrow series finale gave us a glimpse of the Star City of Earth-Prime, which has changed significantly following Oliver Queen’s heroic sacrifice in "Crisis On Infinite Earths," opening up an additional set of challenges.

During a press event attended by CBR and other outlets, Arrow producers Marc Guggenheim and Beth Schwartz, who also wrote the finale, explained how they decided what changed in Star City, while also making sure they left options for the potential Green Arrow and the Canaries spinoff and other Arrowverse series.

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“We've had a lot of discussion about what's new [on Earth Prime],” Guggenheim said, “but at the same time, because we have possibly the [Green Arrow and the Canaries] spinoff and there's also all these other sister shows, we've given ourselves the freedom to be like, 'OK, just because we've had these conversations… doesn't mean that we're foreclosing a great idea if one comes along.' Because we've always given ourselves permission to deviate from the plan if someone in any of the writers rooms comes up with an awesome idea, which happens, quite frankly, all the time.”

“But we did have large conversations just in Arrow [about] the characters who were dead and the ones that we were bringing back… we were really setting the rules,” Schwartz added. “And we spell it out in the finale that it's the people who were important to Oliver that have come back, but that doesn't mean… we won't surprise you if the spinoff goes or on the other shows if there is another character that might come back.”

One notable character who didn’t return in the series finale was Earth-1 Laurel, something even the Laurel from Earth-2 questioned. According to Guggenheim, the decision to forego a return by Earth-1 Laurel wasn’t easy, but was ultimately the result of specific considerations.

“We went back and forth on that a great deal,” Guggenheim confessed, “and truth be told, that was really driven by the spinoff. I think if we weren't doing a spinoff we probably would have gone a different way. But we had a lot of conversations [about] which version of Laurel did we want in the spinoff, and we've really fallen in love over the years with the Earth-2 version of Laurel. We love [actor] Katie [Cassidy]'s take on that character. We love writing for that character. We love the complexities of that character’s moral seesawing. She's just always been a more interesting character to us.”

“And as well as... in Seasons 7 and 8, she was really able to redeem herself,” Schwartz continued. “And we felt that that was such an important story for her character. And she's come such a long way from murdering people all the time to becoming the hero. You know, she was at the end of Season 8 and will continue to be in the spinoff, hopefully, and so it just felt like we would short-change her if we didn't really honor the growth that her character went through.”

Guggenheim also noted that even with the changes to the Arrowverse, they attempted to write Arrow's series finale in a way that would still uphold the show fans had followed for over seven seasons. “One thing we didn't want to do was invalidate the entire series,” he said. “There's 169 episodes that come before this one, and all those stories happened. You can watch knowing everything.

“I think, in my mind, things would be different if this was just the eighth season finale and not the series finale,” Guggenheim continued. “If we were doing a Season 9 and suddenly Tommy and Moira and Lance are all back then, yeah, [viewers would be] like, 'Why did you jerk me around for eight seasons?' But we're not telling those stories. There isn't the ninth season of Arrow. There is no more Oliver Queen. So, this just felt like a way to honor the completion of Oliver's mission, a mission that included going through all of these losses.”

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Guggenheim acknowledged that bringing together all of The CW’s current DC TV shows on one Earth creates a new challenge for the Arrowverse. “Because we're now all on Earth-Prime it’s, I think, more beholden on us just to try to acknowledge all the other shows going forward. And I think that's part of the fun. One of the things we've talked about [is] how do we create more cohesion among all the shows so you really feel like you're living in a shared universe. But that, to me, is what's really exciting, and I think all the other showrunners share that.”

Arrow stars Stephen Amell as Oliver Queen, David Ramsey as John Diggle, Rick Gonzalez as Wild Dog, Juliana Harkavy as Black Canary, Katie Cassidy as Black Siren, Katherine McNamara as Mia Smoak, Joseph David-Jones as Connor Hawke and Ben Lewis as William Clayton-Queen. Arrow’s final episode is available to stream on The CW app.

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