The subpages linked here detail some numbers and requirements linked to completing the Pokédex in each of Diamond, Pearl, and Platinum.
The ultimate goal of the Professor Oak Challenge.
In Mystery Dungeon, I often strive to recruit as many Pokémon as possible at the evolutionary stage I want them at, no matter their spawn rate, and evolve only the ones I can't get otherwise. These pages outline what Pokémon can be obtained with a similar approach to Diamond, Pearl, and Platinum.
Although the Sinnoh Pokédex can be completed, the National Pokédex cannot be completed with only Diamond, Pearl, and Platinum. These pages discuss the greatest possible number of Pokémon that can be obtained despite that fact.
The four Regis (Regirock, Regice, Registeel, and Regigigas) either require transfer from Ruby, Sapphire, or Emerald, or the support of event distributions. All other Pokémon can be obtained in the five Gen 4 games.
Although the Sinnoh Pokédex can be completed, the National Pokédex cannot be completed with only Diamond, Pearl, and Platinum. These pages discuss the greatest possible number of Pokémon that can be obtained despite that fact.
The four Regis (Regirock, Regice, Registeel, and Regigigas) either require transfer from Ruby, Sapphire, or Emerald, or the support of event distributions. All other Pokémon can be obtained in the five Gen 4 games.