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A huge earthquake caused by a strange virus has stricken the Sunshine and Dark Moon districts, damaging the access points to the Digital World and causing many Digimon to mysteriously degenerate into Digi-Eggs. In Dawn, rumors have spread that the Night Claw Team (referred to in game as Night Crow) from Moonlight District (Referred to as Darkmoon), were responsible for the incident and vice versa for the Light Fang team. With both sides accusing the other, players will take the role of an opposing tamer to investigate and uncover the truth behind the dangerous tremors.

Note that although the games will share a main story, it is known that the plot will differ between Dawn and Dusk to some degree. Players will also explore different areas depending on the version of the game they play. You may choose to play as a boy or girl, though the boy and girl look slightly different depending on the version you play. The two games will feature parallel storylines with a main team in each that opposes the other (Light Fang in Dawn and Night Claw/Night Crow in Dusk), though the two teams work together towards a common cause.

[edit] Starter Digimon

Depending on the version of the game being played, players automatically begin with whichever lead Digimon is exclusive to their version, plus two Digimon from the respective packs chosen. Coronamon is Dawn's starter and Lunamon is Dusk's.

The way to progress in the story is by taking union hosted quests. A good way to get some useful items and train your Digimon is to take quests helping a specific type of Digimon depending on the version you are playing.