Social media reacts to all those big moments (and that guest star) on Crisis on Infinite Earths

Whoa! So, we all knew that The CW's Crisis on Infinite Earths would have a ton of surprises, Easter eggs and special guest stars. But last night’s conclusion to the crossover event had some surprises that even one of its stars didn’t expect!

*Major spoilers for last night's episodes of Arrow and Legends of Tomorrow.*

So, last night's episodes of Arrow and Legends of Tomorrow featured a ton of shocking moments, from the (second) death of Oliver Queen to the formation of the Justice League to a guest spot from none other than Ezra Miller, The Flash from the big screen Justice League, tying the Arrowverse and cinematic DCEU together.

Not surprisingly, many fans took to Twitter to pay their respects to Queen (Stephen Amell).

Fans were also elated about the formation of the Justice League…

And as for Miller’s surprise appearance as The Flash, well…

Regarding this last surprise, The Flash star Grant Gustin took to his Instagram page to post some selfies with his alternate self.

"How about that?” Gustin wrote alongside three photos. “Ezra is one of a kind. So glad we could make this happen and keep it a secret until today. Thank you to @dccomics.”

Apparently Miller's surprise guest spot was such a well-kept secret that even Supergirl's Melissa Benoist didn't know about it until it happened.

Benoist commented on Gustin's post: “YOU KEPT THIS SECRET SO WELL,” she said. “NONE of us knew!!!! Or did they know?! Was I the only one that didn’t know?!”

Bottom line? Seems like Crisis made a lot of Arrowverse fans happy.

And oh, yeah, there was also this…