This year at San Diego Comic-Con, one of the biggest phenomena isn't just inside the convention center, it's all around. Yes, there are billboards and installations trumpeting things like Doctor Strange and Fear the Walking Dead. But the crowds of people here aren't looking up; they're mostly staring down at their phones, playing Pokémon Go.

In fact, the overwhelmingly popular game has pretty much taken over the informal economy of Comic-Con. There are always people outside the convention grounds selling glow sticks or jewelry or their own homemade paintings of Batman. This year, if you join the slow-moving crowds heading across the tram tracks from the convention center to San Diego's Gaslamp Quarter, what you'll see is hawker after hawker with Pokémon merchandise — and, in a wise marketing move, portable phone chargers for everyone who's drained their batteries hunting Growlithes and Bulbasaurs.

Head further into the Gaslamp Quarter, where bars and restaurants cater to the tens of thousands of convention goers, and you'll see more ways people are capitalizing on the catch-em-all fad. Outside a bar on Fourth Street, a sign lists of all the rare Pokémon that have been caught inside. A few blocks over, another bar has surrounded its outdoor seating with a massive temporary mural of Superman surrounded by cute cartoon monsters.

There's a sweet spot for Pokémon Go players along a pedestrian path across from the convention center; a series of plaques with quotes from Martin Luther King, Jr., have been marked by PokéStops, the virtual landmarks where players can get in-game resources (whether they read the quotes is another matter). In the evening when the fierce heat fades, crowds of players — some in costume — line the path.

Sisters Gretchen and Samantha Cash decided to make the virtual landmarks a reality. "PokéStop, PokéStop, real life PokéStop!," they call out to the crowd. "We got berries, free berries! Come get your berries! Yaaay!" (Berries are an in-game resource that make the little monsters easier to catch.)

The sisters are from San Diego, and they're avid Pokémon Go fans.
"We constructed an actual physical PokéStop ... out of paper," Gretchen says. "And then we let people spin it and we give them berries," although instead of digital berries, they're handing out Starburst candies.

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