Whenever the PlayStation Store comes back online in Japan, Nippon Ichi will have a ton of downloadable content ready for Disgaea 4: A Promise Unforgotten. Pleinair, Prism Red, and the Celestial Host are ready to be released as DLC.
Fans of the Prism Rangers can also purchase ship parts for the Space Battleship Gargantua and tiles to create maps inside the Space Battleship Yamato inspired ship.
Another new feature is a survival-like mode where you can consecutively challenge other players. These battles are similar to online duels, but you cannot recover or call allies for reinforcements. As a bonus you can double your CP with each fight you win. Get over 5,000 CP and you unlock Pleinair.
The tournament battle system costs 600 yen ($7.50). Pleinair cannot be purchased separately, but the other two downloadable characters are 300 yen ($3.75) a piece. Space Battleship Gargantua ship parts are 200 yen ($2.50) and the tileset is 100 yen ($1.25). The Toro Bow pictured below is free.