The "Crisis on Infinite Earths" Arrowverse crossover rebuilt the Multiverse, merging many of the Earths together so the stars of ArrowThe FlashSupergirlBatwoman and DC's Legends of Tomorrow now all live on the same Earth. The event also featured Easter eggs to various DCTV properties past and present, including TitansDoom PatrolSmallvilleBirds of PreyLucifer and many others.

The news came out that a DCTV series that wasn't represented in "Crisis on Infinite Earths" would get a shoutout in the Arrow series finale, and consulting producer Marc Guggenheim confirmed it's the short-lived NBC series, Powerless.

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Guggenheim explained to DCComics.com why a Van Wayne Industries billboard appeared in the background during a nighttime scene between Thea and Roy Harper.

"To cover something up (when shooting on location), usually we put up a billboard and we’ve trained the art department over the course of eight years to look at it as an Easter egg opportunity," Guggenheim revealed. "By this point, we were through with “Crisis.” I was completely spent. I'm like, “I don't know if I have anything left in me.” So, I called up DC’s VP of Creative Affair and Creative Services, Dan Evans, who's been my partner in crime for so much of this. I'm like, “Okay, Easter egg for the Arrow finale. What do you think?” And that was his pitch. So, I’m like “Great. Wonderful. Done.” It was like anything I can also clear at this point, let's do that. But also, I love that show, so it worked out really well. And that's the truth—the good, the bad and the ugly behind that Easter egg."

Powerless aired for one season on NBC in 2017. It released 12 episodes and focused on Vanessa Hudgens' Emily Locke, who worked for a Wayne Enterprises company called Wayne Security. The series focused on what it was like for everyday people to live in a world with heroes like Superman and Batman.

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.

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