New Super Mario Bros. U and its downloadable content New Super Luigi U will be getting the combo pack treatment later this year. The Luigi U expansion had previously launched as both DLC and in a standalone, physical format. The New Super Mario Bros. U + New Super Luigi U bundle will release on October 16 in North America. They'll be a perfect purchase for Mario fans who are new to the Wii U, especially those who are looking to pick up the Walmart-exclusive Super Mario Maker Wii U bundle, launching September 11.
Source: Nintendo (via Nintendo Everything)