You'll find it in the place where the safari zone was, in Kanto.
You can't migrate from HeartGold to Ruby. But it can be the opposite. Pokemon can be migrated from Pokemon Ruby to Pokemon HeartGold.
to palpark in fusha city where the pioson gym leader is.
If you have Pokemon heartgold, you cannot get groundon unless you trade with someone who caught a groundon on soul silver. PS- It has to be from the embedded tower, any migrated groundon will not work.
All those pokemon would need to be migrated to Heartgold/Soulsilver.
Once you migrate from R/S/E, you go to Fuchsia City to the Pal park at the top of town. There you can catch your pokemon. =D
In Heartgold or migrated or AR code
You can only catch lugia if you migrated it from firered or leafgreen. If you want lugia get one from heartgold or soulsilver version.
There is no best Pokemon on Pokemon HeartGold.
there is no Pokemon Mansion in Heartgold.
They are not in Pokemon HeartGold
Go to the Pal Park and you can 'catch' the Pokemon you migrated from there.
where is the pokemon transfer lab in heartgold