Nintendo Switch gamers have been eagerly awaiting the arrival of the service due to the availability of classic games like Super Mario Bros. and The Legend of Zelda. However, hackers managed to crack the app's emulator, allowing anyone to install their own NES ROMs and successfully play them on the Nintendo Switch.
A hacker by the name of DevRin uploaded a short clip to YouTube showing the game Battletoads running without issue. You can see a brief clip below:
Interestingly, the actual Switch Online app lists compatible NES games as .NES files in plaintext. This plaintext database can be modified, which allows you to add your own ROM files.
“For someone without prior experience in running Switch mods, getting all of it set up at first is a bit of a process, but nothing too hard with proper instructions,” said hacker KapuccinoHeck in a statement to Polygon. “After an initial setup it’s insanely easy to swap out ROMs and add entirely new ones.”
While modifying the database file might seem trivial, the process of actually getting the games onto your Nintendo Switch isn't exactly straightforward. For starters, your console has to be hacked, which brings with it a whole new set of potential downsides -- namely the constant fear that Nintendo will blacklist your device.
“From what I’ve been told, there’s a fair amount of telemetry and checking on the app for a valid setup, but ultimately I’m unsure,” KapuccinoHeck added. “Nintendo is very unpredictable when it comes to these things so for now I would heavily advise against anyone else doing it.”
In other words, proceed with extreme caution. While playing classic NES games on your Nintendo Switch (that aren't currently offered via Nintendo Switch Online) is awesome, it's not worth being blacklisted by Nintendo. Besides, you can just go out and buy a $60 NES Classic Edition console and hack it to your heart's content if you want to go hog-wild with NES ROMs or just use an emulator on your PC.