After months of waiting, the second wave of DLC is available now for Mario Kart 8 Deluxe. Those wishing to play the new courses will be required to update the game to the latest version, ver 2.1.0 and we have the full patch notes, right here:
Ver. 2.1.0 (Released August 4, 2022):
Support for DLC:
- Now supports paid DLC: Mario Kart 8 Deluxe – Booster Course Pass, Wave 2 (two cups and eight courses).
General:
- Increased the number of ghosts you can download from 16 to 32.
- Adjusted the extent to which a vehicle is thrown, depending on its weight.
- Further shortened the time it takes for item boxes to regenerate after another player takes them.
- Shortened the time it takes for one player to be able to pick up a coin that another player has dropped.
- Made it so that it is easier to face the way forward in mid-air when using Smart Steering.
- The cars that the Shy Guys are riding in in Wii Coconut Mall now move from time to time in all modes other than the Time Trial mode.
Fixed Issues:
- Fixed issue where player could not choose a DLC course even though a player in the lobby in “Friends” has the Booster Course Pass.
- Fixed issue where player did not receive coins even though they used the Feather in Coin Runners to steal a rival’s coins.
- Fixed issue where player could receive two items from one item box in N64 Toad’s Turnpike.
Source: Nintendo