As the new coronavirus spreads internationally and the more creative (or paranoid) among us are threat-mapping our daily routines, gyms have become a big, fat question mark. It’s a great time to hone indoor workout routines, which, for owners of the Nintendo Switch console, might mean finally investing in Nintendo’s workout game, Ring Fit Adventure. Good luck finding it.

Bryan McFarland, a 33-year-old in Mesa, Arizona, started looking for a copy of Ring Fit Adventure three weeks ago. Covid-19 wasn’t yet as urgent a threat in the US; he just wanted a way to work out in the privacy of his home. He swung by Target, but it was out of stock. The nearest one listed online as selling Ring Fit Adventure was in Dallas, a 15-hour drive east. It soon disappeared. Nearby Walmarts didn’t have any. The six GameStops he called didn’t, either. McFarland began searching online—eBay, Amazon—and saw that the few third-party vendors that had it in stock were selling it for up to $220. It retails for $80.

It took two weeks for McFarland to track down an affordable copy of Ring Fit Adventure. He eventually drove 35 minutes to the parents’ house of a guy he met over the app OfferUp with $100 in cash.

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Released October 2019, Ring Fit Adventure is a role-playing game in which players traverse beautiful worlds and combat monsters, all by exercising. The game monitors players’ movements using a leg strap that contains a motion-sensing Nintendo Switch controller and a big, bendy resistance ring. It’s a lot like what you’d see in a pilates class, plus cartoonish dragons. To pummel enemies, players must squat, do yoga poses, jog, or flex their arms. It’s a cute game, an ass-kicking exercise, and a welcome escape route for those fearful of gym sanitation.

Since Friday, the average price of Ring Fit Adventure on eBay has surged to $130. The game is unavailable at GameStops within 100 miles of New York City, Los Angeles, Chicago, Atlanta, Houston, Phoenix, Des Moines, Las Vegas, and Seattle, according to GameStop’s website. The second and third entries on Amazon are for $500. More affordable listings on digital marketplaces tend to be for knock-offs of Ring Fit Adventure’s controller hardware and do not include the game. (They have red and blue handles on the Ring, rather than gray. Amazon especially is rife with them.)

This is not just a story of increased demand. Nintendo outsources a lot of its manufacturing to Chinese businesses, and in early February Nintendo told fans that the coronavirus would impact production and shipping for the Nintendo Switch. In the same post, Nintendo explained that Ring Fit Adventure was out of stock. In some online marketplaces, the game is now as valuable as an actual treadmill.

In China, where Covid-19 is far more widespread, the shortage is worse. Daniel Ahmad, a senior analyst at games industry analyst firm Niko Partners, says that even though Ring Fit Adventure has not received an official release in China, demand for it has soared since the outbreak began.

“Resellers are purchasing large quantities of the game from Japan, Asia, Australia, and the rest of the world and then selling them to Chinese consumers on sites such as Taobao. Some of the top individual stores online have sold more than 1,000 units in the past month on Taobao,” says Ahmad, referring to an eBay-like website. Ahmad shared a graph that maps Ring Fit Adventure’s price in China going from the equivalent of $115 American dollars in early January to $287 today.