The Wii U version of Sonic Lost World will have two exclusive DLC packs based on two Nintendo franchises. The first is already out- Yoshi's Island Zone. As Sonic, you'll race through levels themed after Yoshi's Island, collecting coins, avoiding piranha plants, and running through pipes and loop de loops alike. This DLC is free to anyone who already owns Sonic Lost World.
Although nothing official has been released, it has been hinted that the next Sonic Lost World DLC will involve The Legend of Zelda and will drop some time in 2014.