Klei Entertainment has announced that a Special Edition of Mark of the Ninja will be available as DLC on Xbox LIVE Arcade and Steam. It contains a new level set in a flashback to the early life of Dosan (the ninja's tattoo artist) that will set the stage for the events that transpire in Mark of the Ninja. Mark of the Ninja Special Edition also features a new style of play, which includes a nonlethal takedown ability and provides a hybrid of lethal and nonlethal approaches to the game. Furthermore, the DLC offers two new items, one more geared to stealth and concealment and one a bit more direct. Both the items and the new play style will be available in the main game as well as the new level (more details at a later date).
Mark of the Ninja Special Edition will be released this summer (price still TBD).