Flash Invaders: One other sport for a world on break


"It's so satisfying when I take a picture and hear the little sound," said Ms. de la Rochefordière.

There are over 1,000 mosaics in Paris where the first pixelated alien entered the Bastille neighborhood in 1996. For a long time, the retro tiles have rewarded attentive Parisians with color drops in the otherwise subdued city, mostly on street corners, but also under bridges and of-the-way curbs on outside streets. When the artist introduced the mobile game in 2014, what was once private satisfaction turned into a community sport.

There is a hunter for every casual stroller like Ms. de la Rochefordière. "I spend so much time on Google Street View that when I arrive I feel like I've already been there," said Stéphanie Aubert, 50, a Marseille journalist ranked 102nd out of 151,000 players.

Invader’s thousands of mosaics outside of Paris are a boon for those who travel often and have a knack for adventure. Completeists must snorkel for underwater invader installations in Mexico and attend live events such as the taping of “The Late Show With Stephen Colbert,” which the artist left a mosaic on in 2015.

The game brought fans together – some closer than others. Denis Gettliffe-Perez (50) and Mélanie Perez-Gettliffe (48) met in 2017 in a Pink Panther mosaic in the 11th arrondissement. "We weren't looking for love and Invader offered it to us," said Ms. Perez-Gettliffe. (They married in December 2018.)

New mosaics have surfaced during the pandemic. Invader visited Marseille in August and gave the locals dozens of new squids and other Mediterranean-themed mosaics to collect. Ms. Aubert thought the invasion was a bit of a cliché – all those sun-drenched pastis bottles – but was impressed that the artist made it beyond the port of Vieux to the working-class neighborhoods to the north.

"It was great to see his choices in a city that I know so well," she said, noting that his works of art are also her guide to other places like Djerba or Hong Kong. "I'm actually a pretty bad tourist, but that gives me a purpose."