A Nintendo Switch Online subscription is necessary to play online multiplayer games on the Switch, but some may be signed up for it primarily to play its library of retro games. Nintendo Switch Online subscriptions get players access to classic NES and SNES titles, while those that sign up for the pricier Nintendo Switch Online Expansion Pack also get access to Sega Genesis and Nintendo 64 games as well.
Rumors have been persistent that Nintendo plans on expanding the retro games available through Nintendo Switch Online in the near future by adding games from its handheld systems. Recently, there's been evidence that Game Boy Advance games could be coming to Nintendo Switch Online in particular, and while an official announcement has not been made, it seems a whopping 39 games have been tested for it.
Rumor: Nintendo Switch Online May Be Adding Game Boy and Nintendo 64 Connectivity Features
Dataminer MondoMega has discovered a list of Game Boy Advance titles that have been tested for Nintendo Switch Online. It includes nearly all the major Game Boy Advance games that one would expect to see from such a service, including heavy hitters like The Legend of Zelda: The Minish Cap, Metroid Fusion, and more. However, fans should keep in mind that even if Game Boy Advance games come to Nintendo Switch Online as rumored, there's no guarantee that all these titles will be included.
Based on how Nintendo has released the Nintendo 64 games on Nintendo Switch Online, it's likely if GBA games come to the service, they will be staggered. What this means is that instead of all the GBA games coming at once, there will be a handful to start with, with more added on a monthly basis. But again, Nintendo hasn't announced any plans to bring GBA
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