According to the developer, the studio wondered "what a "Criterion Collection" version of the game would look like, and that's how we've approached Mark of the Ninja Special Edition."
The new mission is set before the events of the game, as "a flashback to the early life of Dosan (the enlightened tattoo artist) that will set the stage for the events that transpire in Mark of the Ninja." The level includes a new nonlethal takedown ability, two new items (one aimed at stealth and the other for a more direct approach.)
The DLC will also include developer commentary (a choice of English, French, Italian, German, Spanish, or Japanese) to the main game in the form of nodes that can be pressed to activate. The nodes discuss various aspects of the game's creation, anecdotes, at least two history lessons and other behind the scenes info from nearly everyone from Klei.
The Special Edition will be available as DLC on both Steam and Xbox Live Arcade. Gamers will be allowed to preview it at PAX East this weekend. No price has been decided for the DLC.