The big surprise on The Late Show Wednesday night was supposed to be Super Mario Run, Nintendo's imminent $9.99 mobile game that's out December 15 for iPhones and iPads (read TIME's hands-on here). And it was certainly cute to watch Jimmy Fallon breathlessly tap his way through a goomba-filled maze of classic platforms and pipes. But all the while, on the table between Fallon and Nintendo of America president Reggie Fils-Aimé, sat a big yellow box with a question mark. What was under the question mark? It's the Kyoto games-maker's next big thing: a home video games console that's also a mobile tablet you can play on the go.