[Warning: This post contains spoilers from Part 4 of the Arrowverse crossover event, "Crisis on Earth-X." Read at your own risk.]

With every victory comes loss, and the final chapter in this year's four-way crossover, "Crisis on Earth-X," came with a huge one: Professor Martin Stein (Victor Garber). The beloved figure exited the Arrowverse in heroic fashion during Tuesday night's heart-stopping episode.

Stein was shot while battling the Nazis on Earth-X, but not before pulling a lever that would open a breach back to Earth-1, allowing the team to escape. Still alive but in critical condition, Jax (Franz Drameh) merged with him to become Firestorm as a life-saving method. The quick fix worked, but when the team made their way onto the Waverider, we learned that it was only temporary. Stein would not be able to live for much longer, and if they were to remain connected then Jax would die too.

After heartfelt speech — with a quick lesson on astrophysics thrown in because this man is an educator, after all — Stein convinced Jax to let him take the serum which would separate their DNA and spare Jax's life. Reluctantly, the younger Legend watched Stein drink it before passing away.

His death was hard to swallow for our heroes (and anyone with a soul, honestly) who found themselves consumed with grief. It was especially difficult for Jax, who not only just lost a father figure but then had to bear the weight of informing Stein's wife and daughter. (Current status: Feeling attacked because I came here to have fun, not be weighed down to the Earth's core by these heartbreaking scenes.)

With the shocking loss still fresh on everyone's minds, it was up to Oliver (Stephen Amell) and Sara (Caity Lotz) to rally the team to stop the Axis from taking over Earth-1. After a rousing speech from Oliver, the group vowed to defeat Overgirl and Dark Arrow once and for all in Stein's honor.

The Justice League of TV got one last slow-motion hero walk (chills!!!!!) in before the main event: a clash of the leather-clad titans. You asked for a show and they delivered a whole stadium tour. The final throwdown featured everything from team-ups to funny quips to doppelgängers squaring off — it was a whole breakfast spread for the eyes. Who knew Arrow swinging around a steel structure like Spider-Man could be outdone by Killer Frost (Danielle Panabaker) building her own ice road in the sky and surfing her way onto the Nazis' Waverider? But that all paled in comparison to Overgirl imploding and creating a sonic boom in the process. Girl power, am I right?

With the villains of Earth-X finally defeated, it was time to put Stein to rest. In a touching funeral scene, our heroes bid farewell to a Legend with poignant words and a few more tears.

Deep breaths, everyone. You made it through another crossover event!

Supergirl airs Mondays at 8/7c. The Flash and Legends of Tomorrow air Tuesdays at 8/7c and 9/8c, respectively. Arrow airs Thursdays at 9/8c.

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