In order to cover two different aspects of Pokémon Diamond and Pearl, the fourth Japanese expansion of the DP Series was split into two subsets. The first, Moonlit Pursuit, is based on the legendary Pokémon Cresselia and its rivalry with Darkrai, with the name referencing the fact that Cresselia is a roaming Pokémon. The second, Dawn Dash, is based on Leafeon and Glaceon, the two new evolutions of Eevee. The five previous Eeveelutions were also included in the two subsets.
With the expansion split in two, 130 of its 143 cards were also split between the two subsets. 65 cards were available only in Moonlit Pursuit and another 65 were available only in Dawn Dash. Thirteen cards, including Eevee (which was required for its evolutions spread across the two subsets) and the basic Energy cards, could be obtained in either of the subsets.
The cards released in the expansion have spanned a total of three English-language expansions. This was for several reasons: the five-and-a-half month gap between the release of this and Shining Darkness, the previous expansion; the removal of cards from that expansion that were related to the tenth Pokémon movie; and the fact that, at the time of its release, Darkrai had not been officially announced in English-language territories.
The first cards from the expansion were released in Secret Wonders: these were Weavile, Gardevoir, Gardevoir LV.X and Honchkrow LV.X. Roselia, Roserade, Magmar, Magmortar, Electabuzz and Electivire from the expansion's half deck were also moved into the expansion. After that, almost all cards from Moonlit Pursuit, as well as several cards from Dawn Dash, were released as Great Encounters, based on Cresselia and Darkrai, as well as the tenth Pokémon movie, The Rise of Darkrai. Finally, the remaining cards from both subsets, along with cards from the Entry Pack '08 and some DP-P Promotional cards, were released in Majestic Dawn.
- The expansion retires the long-standing Mysterious Fossil, which has been in circulation since 1999. In Moonlit Pursuit, the new Helix Fossil card is available for evolution into Omanyte, as are Dome Fossil and Old Amber in Dawn Dash for evolution into Kabuto and Aerodactyl respectively. With this change, all Fossil Pokémon now have their own Trainer card from which to evolve.
- This expansion features the first new Special Energy cards of the DP Series: Call Energy, Health Energy and Recover Energy.
- The contents of the Magmortar vs Electivire Deck Kit spanned the same three English expansions as the two subsets; however, some reprints with alternate artwork were also released in POP Series 7.