To unlock the National Pokedex in Pokemon HeartGold for the Nintendo DS, simply beat the Elite Four at least once and then go to the S.S. Aqua Ship.
About DoubleDizle
Gamer, Software Engineer, Web Developer, Professional Geek
You also might be interested in
Q: How do you gain stars and colors for my[...]
To unlock the National Pokedex in Pokemon SoulSilver for the[...]
Q: Is it possible to catch Mew in Pokemon Leaf[...]