With the crossovers coming up, Arrow show runner Marc Guggenheim stated that he has changed his mind with Arrow being grounded. So now after the crossover, we may see metahumans showing up in Starling City. The following are quotes from Marc Guggenheim

"What's fun about episode 8 for 'Arrow' is it proved to me, as a writer and a producer, hey, you know what? You can do metahumans on 'Arrow' without feeling like the show is changing its tone too much,"
Marc Guggenheim

"It's something that we all sort of collectively realized -- hey, the show can handle that. So that's kind of cool. I might have to amend my earlier comment from the beginning of the year, just because this kind of works."
Marc Guggenheim

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