In case nostalgia over the good ol' years of Sonic wasn't enough to make you key into Sonic Lost World for the Wii U/3DS, how about exclusive NiGHTS content? Yes, over gamescom Sega announced the Deadly Six Bonus Edition which will include "NiGHTMARE DLC." The NiGHTMARE DLC will unlock a level that can be played at any time and features content from NiGHTS Into Dreams.
For some reason it doesn't seem like Sega has released the pricing on the Deadly Six Bonus Edition yet, which makes me think it's just a preorder bonus? You know, like a Day-1 exclusive edition type of deal. Alto take note to say that Sega makes it seem like the NiGHTMARE DLC might not necessarily be exclusive to this package. Perhaps it will be available for a cost as simple downloadable content post-release?
Sonic Lost World is planned for release on October 22 on both the Wii U and the 3DS, though they'll each be different versions of the same game. The Deadly Six Bonus Edition is unfortunately exclusive the the Wii U version of the game. NiGHTS Into Dreams on the 3DS? That would just be silly!
Deadly Six Bonus Edition trailer - Youtube