Thousands of years ago, Arceus stepped in and saved the population of the world, both Humans & Pokémon from a tackling meteor from Outer Space. During the process, it was severely injured and taken care of by a character called Damos. As gratidude, Arceus promised to help make the soil of Michiina rich and turn the land prosperous so gave Damos the "Jewelled Orb of Life". The Jewelled Orb of Life was created by joining the 16 life forces within Arceus' own body (One for each type such as with the plates). Damos was to return the orb to Arceus on a specific date, but Damos betrayed Arceus, perhaps due to his minion Gishin whom has Pokémon with devillish accessories and did not return it. Arceus went to into a deep slumber after this, but carried the rage of the betrayal and vowed to judge the human race based on Damos' actions when it awakens again.

Thousands of years later, the descendant of Damos, a girl called Sheena, is protecting the ruins of Michiina with a man called Kevin, and has the duty to return the Jewelled Orb of Life to Arceus when it's set to awaken. Ash, Brock & Dawn soon come to the land of Michiina during their travels through Sinnoh and end up getting trapped in a water tornado. Sheena sees this and prays to Dialga whom quickly appears and quells the tornado. Sheena takes Ash & Co. to the ruins and explains the different dimensions that are inhabited by Dialga, Palkia & Giratina. However, not long after that, the three dragons soon appear and continue their constant fighting. However, when the fighting gets out of hand, the ruins of Michiina are destroyed, and Arceus is awoken prematurely...