next game. The gameplay system is a departure from the original and employs card game mechanics in real time. Players construct decks out of cards that correspond to different actions in battle, such as attacking or using magic. It was remade into a PlayStation 2 game titled Kingdom Hearts Re:Chain of Memories, which contains polygonal graphics instead of the sprites used in the original game. The remake was released in Japan as a second disc packaged with Kingdom Hearts II Final Mix on March 29, 2007, and in North America as a standalone game on December 2, 2008. Kingdom Hearts II takes place one year after the events of Chain of Memories. It was released for the PlayStation 2 in Japan on December 22, 2005. The game further explores the "heart" concept by involving a new group of enemies, the Nobodies, which are the cast-off shells of those who have become Heartless. The gameplay is similar to that of the first Kingdom Hearts game, with the addition of the Reaction Command, which performs reflex-sensitive actions in battle. Kingdom Hearts II was revised into Kingdom Hearts II Final Mix, which contains more material than the original release, such as additional cutscenes and bosses. Kingdom Hearts II Final Mix was released with Kingdom Hearts Re:Chain of Memories in a collection titled Kingdom Hearts II Final Mix+, which was released in Japan on March 29, 2007. Kingdom Hearts Coded is an episodic mobile phone game that picks up directly after Kingdom Hearts II. The "preinstall" episode was released in Japan on November 18, 2008, and eight episodes were released between June 3, 2009, and January 28, 2010. The game was remade for the Nintendo DS as Kingdom Hearts Re:coded, and features updated gameplay combining that of two later entries in the series, 358/2 Days and Birth by Sleep. Unlike the original version, Re:coded was released internationally: October 7, 2010 in Japan; January 11, 2011 in North America; and January 14, 2011, in Europe. Kingdom Hearts 358/2 Days was released for the Nintendo DS in Japan on May 30, 2009. It is primarily set between Kingdom Hearts and Kingdom Hearts II, focusing on Roxas' time in Organization XIII and his motives for leaving. It is the first game in the series to feature cooperative multiplayer in addition to the traditional use of AI-controlled partners. Gameplay is mission-based with optional objectives that yield additional rewards.