'Supergirl' Sets Up Cataclysmic 'Crisis on Infinite Earths' Crossover for 2019 and Twitter Can't Handle It

As the "Elseworlds" crossover event wrapped up Tuesday night on "Supergirl," it set the stage for something far worse to come in 2019: "Crisis on Infinite Earths."

Longtime DC Comics fans know that this is the name of the groundbreaking 1985 comic book series that literally rewrote the history of the DC Universe, notably destroying every single parallel world to leave only one universe remaining.

Considering how many universes the "Arrowverse" has come to inhabit, that would be a major status quo change to the DC family of shows on The CW. At the same time, it would be a convenient way for the network to finally have "Supergirl" exist in the same universe as "Arrow" and "The Flash."

Hell, if they were feeling really frisky, they could pull "Black Lightning" in as well for its third season and throw that family for a hell of a loop with the introduction of all these new heroes. As for "DC's Legends of Tomorrow"? Well, that could stick with its time-travel theme, and in so doing could start to uncover this new altered and combined reality.

But is the "Arrowverse" brave enough to go down that path? Many fans were left disappointed with the "Flashpoint" event on the television series, as it was far tamer than the reality-altering comic book event on which it was based. But considering their willingness to alter reality for "Elseworlds," maybe they're bolder than we give them credit for.

But there is another problem when it comes to the biggest "Crisis" of them all. Considering the following a major spoiler alert for the comic book series -- and it was enough to convince some fans they don't want to see The CW even coming close to this story.

The original "Crisis" was so reality-shattering that there were heavy casualties, including both Flash and Supergirl. The Flash was replaced by Wally West in the DC comic book universe, while Kara Danvers simply never existed in the rewritten DCU continuity.

Of course, we could argue that by almost having the pair of them die in tonight's "Elseworlds" finale, the Arrowverse has already paid tribute to their sacrifices in the original "Crisis" and we're good now. Honestly, we don't see The CW stripping their reality of both of these characters, no matter what happens.

At the same time, Oliver clearly made a deal with the Monitor to save both Barry and Kara from their destined deaths in this episode. The Monitor said their must be balance, so what did Oliver offer? Some fans think he offered himself up as a sacrifice. He's already told the Monitor that he wasn't who he was looking for; he has too much darkness in him.

On top of that, "Arrow" is in its seventh season, so it's possible that either he or The CW are planning his exit from the DCW Universe, maybe to make room for "Batwoman"? Or we're all just totally overthinking this. Even so, he did clearly offer the Monitor something that convinced him to save Barry and Kara. If not himself, what was it?

The wild ending to this year's crossover and big reveal of next year's event had fans both pumped and terrified, keeping #CrisisOnInfiniteEarths trending on Twitter deep into the night. Check out some of their reactions below:

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