The subpages linked here detail some numbers and requirements linked to completing the Pokédex in each of HeartGold and SoulSilver.
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 HeartGold and SoulSilver.
Although the Johto Pokédex can be completed, the National Pokédex cannot be completed with only HeartGold and SoulSilver. These pages discuss the greatest possible number of Pokémon that can be obtained despite that fact.
Although the Johto Pokédex can be completed, the National Pokédex cannot be completed with only HeartGold and SoulSilver. These pages discuss the greatest possible number of Pokémon that can be obtained despite that fact.