Elseworlds Hints Diggle Is [SPOILER] On Earth-90

John Diggle on Arrow

WARNING: The following article contains spoilers for this week's episode of Arrow, the second part of "Elseworlds," which aired Monday on The CW.

The CW's Arrowverse has grown so much since the 2012 debut of Arrow that it's more surprising which DC comics characters haven't shown up than who has. Still, there are some notable heroes who have yet to appear, including Green Lantern.

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Despite some scattered Easter eggs on Arrow and The Flash, there’s never been a direct reference to the members of the intergalactic police force. Perhaps the closest we've come is a nod in The Flash's first season to a test pilot from Fenris Air who had gone missing, mirroring the origin of Hal Jordan. But in the second part of the "Elseworlds" crossover, The Flash of Earth-90 (John Wesley Shipp) delivers the Arrowverse's biggest shoutout to the Green Lanterns while also dropping a potentially major revelation about a longtime Arrow character. Or at least his analog.

The Ring Thing

After recovering the Book of Destiny from Arkham Asylum, the assembled heroes of Earth-1 create a bridge for The Flash of Earth-90 to race through. He explains that he’s the Barry Allen of his world, and he’s come to warn them about the Monitor's plans.90

The alternate-universe Flash greets John Diggle (David Ramsey) like an old friend, saying, “Where’s your ring?” There are few noteworthy rings in the DC Universe, the biggest being the one worn by members of the Green Lantern Corps. The implication, of course, is that Diggle is the Green Lantern of Earth-90.

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Diggle wasn't based on any preexisting DC character, but the positive reception to him on Arrow eventually led the introduction of a comic book counterpart. But this Easter egg suggests there might be a deeper connection for Diggle to the rest of the DC Universe. Whether that means on Earth-90 he's John Stewart, the fan-favorite Green Lantern who rose to fame on the animated Justice League; a stand-in for another Lantern; or merely a different version of himself will have to remain a subject of speculation, at least for now.

If the Green Lanterns do exist on Earth-90, then they could possibly be present on Earth-1 as well. There have been enough nods that it wouldn’t be surprising, and given the broadening scope of the Arrowverse (seriously, the Legion of Super-Heroes have been introduced), it would be more shocking if the Green Lanterns didn't appear on one of the series at some pojnt. With this confirmation from the Earth-90 Flash, it might be possible that as Diggle will receive a massive power upgrade down the line.

The three-night Elseworlds event concludes Tuesday at 8 p.m. ET/PT on The CW with Supergirl.

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