http://www.gamespot.com/news/sonic-lost-world-deadly-six-edition-revealed-6413491

Sega today announced the Sonic: Lost World: Deadly Six edition, a premium bundle available only for those who preorder the upcoming Wii U game.

The Deadly Six edition features the NiGHTMARE downloadable content, inspired by the classic Sega Saturn game NiGHTS into Dreams.

The NiGHTMARE DLC is an exclusive level accessed by a redeemable code. In the content, Sonic must defeat the Deadly Six, enemies riding hulking nightmaren monsters.

The content can be played at any point in Sonic: Lost World, Sega said. When this level is completed, players will have access to a special Color Power, usually attainable only through Miiverse.

Sonic: Lost World launches for the Wii U and 3DS in October.