Marona of Phantom Isle, which can be accessed from the Dimension Guide service in-game, puts Prinny on a nice, colorful island filled to the brim with baddies. For those of you that aren't devoted NIS followers, Marona is one of the main characters in Phantom Brave, a strategy RPG released several years ago. Marona is a young girl that has the ability to see phantoms, including her ghostly guardian, Ash.
The stage in the Marona DLC doesn't offer anything revolutionary that players haven't seen before from the standard levels. Marona's level is much more about navigating the terrain while fighting off opponents than it is about executing crazy jumps. However, there's one absurdly difficult section towards the end of the stage.