WARNING: The following article contains spoilers for The CW's Crisis on Infinite Earths, streaming now.

There was a lot of buildup to the CW's "Crisis on Infinite Earths." The first hint the Arrowverse would eventually adapt Marv Wolfman and George Perez's iconic event of the same name was given in The Flash's pilot in 2014 with a newspaper saying the Scarlet Speedster would vanish in 2024. However, that date got moved up massively. At end of last year’s Elseworlds crossover, a title card revealed the Crisis would now take place 2019, which was further reinforced by the goings on in various Arrowverse series.

Teasing the event for so long meant fan expectations were high and, although there will still rough edges, "Crisis on Infinite Earths" lived up to the hype in a lot of key areas, setting the bar for future crossovers ridiculously high. Here are some of the ways "Crisis on Infinite Earths" excelled.

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Crisis on Infinite Earth Had Unbelievable Guest Stars

Ezra Miller as The Flash on Crisis on Infinite Earths

Characters from just about every DC movie and TV universe appeared in "Crisis on Infinite Earths." Some of those were cameos that barely lasted a scene (Titans, Doom Patrol, Swamp Thing, Stargirl, Batman '66, Batman 1989 and Birds of Prey), but others were much more substantial.

Smallville's Tom Welling appeared as Clark Kent, frustrating Lex Luthor and giving his character a great send-off, and Kevin Conroy appeared as Earth–99 Bruce Wayne, giving Kate a reminder not to go too far in looking for justice. Earth–96 Superman, played by Brandon Routh, had a huge role in the crossover and was heavily inspired by Kingdom Come, though with a better, happier ending. There was even Ezra Miller as the DC Extended Universe's Barry Allen, providing a moment of comedy at the bleakest part of the crossover.

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The Crossover Put the Focus on Its Characters

Although the premise for "Crisis on Infinite Earths" is dark and bleak, the crossover never got too miserable and didn't wallow in that feeling. The cameos were often joyous, and Lex Luthor brought a twisted sense of humor to the proceedings. The crossover put a lot of focus on characters and showing how they interact with each other. Plus, there was a lot of focus on advancing character's stories and really focusing on them. There are the obvious leads of the main shows, but even less central characters like Nash Wells/Pariah, Earth-96 Superman, and Earth-90 Barry Allen got to carry big moments.

However, no one had a bigger moment than Oliver Queen. The Arrowverse was always clear "Crisis on Infinite Earths" would kill Oliver. While his first death was surprising and a bit off-putting, his final death at the end of Part 4 of "Crisis" was much more satisfying. Oliver had an incredible journey, starting as a billionaire playboy shipwrecked on an island and ending up as a cosmic being sacrificing himself to save many universes. Being the character that started the Arrowverse and served as its namesake, it’s fitting Oliver dies giving everything to save everything.

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The Arrowverse Could Take A Lot of Different Directions

"Crisis on Infinite Earths" sets up a lot of future possibilities for the Arrowverse. The montage showing all the new/returning Earths acknowledges the various other DC Universe shows are in the multiverse, leaving open the door for there being more substantial crossovers with them going forward. However, the event also changes the dynamic for the main Arrowverse shows. Supergirl and Black Lightning are no longer taking place on separate Earths -- they’re all part of Earth-Prime.

This finally pays off an idea set up in the Invasion! crossover: A version of the Justice League influenced by the Super Friends (there was even a Gleek cameo)! In a STAR Labs Research Facility that looks suspiciously like the Hall of Justice, there's a table for the Arrowverse's version of the team, which features The Flash, Superman, Black Lightning, Batwoman, Martian Manhunter, Supergirl, White Canary and an empty seat for Oliver. Given the logistics of trying to produce these events, don’t expect the shows to crossover all the time, but after years of teasing the Justice League, the CW is finally embracing the superteam.

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Although its immense ambition could have left fans disappointed, "Crisis on Infinite Earth" stuck the landing and was both a status quo shattering crossover and a great story, giving fans just about everything they could ask for.

"Crisis on Infinite Earths," the latest five-show crossover between all the Arrowverse series, is available to stream now on The CW.

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