We’ve seen something new with pretty much every DLC wave for Mario Kart 8 Deluxe. In Wave 2 we saw a brand new race track in the form of Sky-High Sundae; in Wave 3 we got new menu options with the item toggle; and now in Wave 4 we are seeing a new (classic) character being added: Birdo! Which is a great surprise for most as Nintendo never mentioned characters would be added as part of the DLC.
As such, Nintendo has now confirmed during a press release that “returning characters from the Mario Kart series will be added in future waves. “ How many? That we can’t confirm, but I think we can safely say that we’ll see some of the characters featured in Mario Kart Tour, which is the game Nintendo is using to pull a lot of its content for Mario Kart 8 Deluxe.