There’s a crowd standing outside the Opera House. On their own, each person looks like most idle people do these days, completely absorbed by their smart phones. Together they look rather peculiar, like an artwork commenting on societal detachment. Suddenly, one guy in a brown beanie and a weather-inappropriate T-shirt-and-shorts combo yells out, “Pikachu!” and starts running. About 30 people follow him up the hill. This isn’t an unusual scene at all. It happens most days, now.

Of course you’ve heard about Pokémon Go by now, the new augmented-reality smartphone game where players catch, train and battle Pokémon at real life locations, based on actual climatic conditions and, literally, by walking everywhere. If you’re not playing it, some of your friends will be. At the very least you’ll have noticed it clogging your news feed. If you still don’t know what it is, start here. Without anyone really expecting it, the game’s already had an enormous impact on Sydney and other cities around the world. Here are some stories.

Dave Liddell, 31, on how spaces are being used differently
Player name: #GeilMupse

Liddell is a busker at Circular Quay and the Opera House, or as he calls it, Ground Zero of the “Pokepocalypse”. “It's that ridiculous. I'm just waiting to get a coffee now from City Extra and I turn around and see 14 people [playing] just between Wharf Three and Four, and I'm playing as well while I talk to you." Since the game launched the entire strip from Darling Harbour to the Opera House area has been completely swamped with Pokémon hunters. “The word is, the bigger the landmark, the rarer the Pokémon and the more Pokémon you can find.” At the Opera House itself there’s a constant crowd of 60 people every day, with a lot more during office lunch hours, he says. The game is barely a week old and it has already redefined the use of our biggest landmarks. “This is definitely going to last. There's, what, 1000 Pokémon? But this release has only given us 150,” says Liddell.

Adam, 23, on what happened in Rhodes

Landmarks aren’t the only locations that have been redefined. Usually empty local parks, playgrounds and squares are now community hubs for Pokémon players. None more so than Peg Paterson Park in Rhodes. “I live in Burwood and I usually go to Burwood Park every night, but I'd been catching crap Pokémon. Duduos, Zubats, just absolute shit. We heard Rhodes was going off,” says Adam. “The traffic was ridiculous, there was no street parking. It's very unusual for that day and time." He didn’t know where in Rhodes to go so he opened the app and saw three Pokéstops (where you get “items” such as Pokéballs, potions and Pokémon eggs) with lures attached (these attract extra Pokémon) in a small park between three apartment buildings. “You just walk and see it. It's crazy. It's like a grand-final atmosphere,” he says. “Every time a Pikachu showed up on the map everyone is shouting and screaming. It's ridiculous, everyone is patting each other on the back. It was awesome, so fun.”

This was at 10.30 at night. Later the same evening Adam says the crowd was water bombed by one of the nearby apartment residents. “I saw people running and we all got a bit confused. About 50 or 60 of us got startled. It was like a carpet bomb, we were under attack,” he laughs. “But 15 minutes later it stopped and we all came back.”

It was more serious for residents there who later (after Adam had left) called the police. "A number of people were asked to move on following noise complaints from residents in the early hours of Sunday. For the most part, the crowd of more than 100 people was well behaved,” says a NSW Police spokesperson. As Adam says, “It was a really good vibe, man. Everyone was giving tips, there were kids walking around and families.”

Adam asked to have his last name and handle removed because he works for a rival video game developer.

Louis Lepper, 22, on getting a date
Player name: #louislepper22

Some interactions have led to more than finding rare Pokémon. Louis Lepper, a software developer, was walking home last week when he spotted a group of eight people playing Pokémon Go in Chinatown. Being a pretty social guy, he asked them if he could join in. “It immediately breaks the tension. Most groups of people seem quite happy for you to hang out with them if you're playing Pokémon Go.” He ended up going with the group to Barangaroo (walking long distances is rewarded by the game). “Half the group defected but a girl from Taiwan was living in Ultimo, so I walked her back. We got on quite well so we exchanged WeChat and met up the next night for a date.”

They met for dinner and ice-skating. “At the very end of the date, as we were walking back, we played a bit of Pokémon Go too,” says Lepper. “I can easily see how I can make more friends from this. I think it's really cool.”

Guy Blomberg, 35, on random interactions
Player name: #Yugstar

Blomberg was one of the co-organisers of Sydney’s first Pokémon Go walks, a group hike where everyone involved cooperates in capturing Pokémon and taking gyms (team-based Pokémon strongholds based on real-world locations). To Blomberg’s surprise, the event blew up. The few hundred people he expected ballooned to several thousand and Pokémon Go Walks are now regular events. That wasn’t the moment he realised the game had become the phenomenon it is, though. It happened a few days after the game launched. “We live near a large park; a bunch of us decided to walk over and hunt for Pokémon. This was at midnight. And it was raining,” he says. “Halfway into the park we noticed some other people in the darkness, walking towards us.” He says they were shady-looking characters and, it being midnight and in the middle of a dark, empty park, he was pretty concerned. Until he saw the glow of several iPhones illumining their faces. “I’m not sure which one of us said it, but someone yelled ‘Pokémon Go?’” They were fellow players, out at midnight, in the rain, hunting Pokémon.

James, 20, on reuniting with old friends

James’s local church is a Pokémon gym. At around 10.30pm he noticed it was being taken over by a rival team. He ran out to defend, only to find the original attacker had absconded. Instead he found a childhood friend he hadn’t seen in 10 years, preparing to attack. “I say nonchalantly ‘That’s my gym, you’re not going to be taking that away from me, Mason’.”

Sometime later, while the two of them were chatting and battling, another person approached the church. “I looked up and noticed that it was my friend Christie, who I also hadn’t seen in over 10 years. I was shocked.” Christie and Mason were on the same team, so between the banter and stories the battles continued. Eventually the trio called it a draw when neither team could claim a decisive victory. They exchanged numbers and went their separate ways. But James went back to the church-gym. “I headed right back to the gym and defeated their Pokémon and went home, laughing. It has been almost a day and my Pokémon is still up there with the name, Sorry Mason.”

James requested his full name and Pokémon handle not be used.

The Opera House will host a Pokemon Go gathering on Wednesday July 20. Between 12pm and 2pm they will be adding lures to all nearby Pokéstops.