what is nintendo switch online expansion pack

The Nintendo Switch Online Expansion Pack is a paid membership that includes access to classic Nintendo 64, Game Boy Advance, and Sega Genesis games, along with select DLC. It also includes all the benefits of a regular Nintendo Switch Online membership, such as online play in compatible games, access to a selection of classic NES and Super NES games with online functionality, and the ability to back up save data for most games. The Expansion Pack membership starts at $49.99 for 12 months and allows access to additional benefits like exclusive special offers from Nintendo.