Sprout Tower, the tower you find Ho-Oh in, or on certain routes in your Pokewalker.
Gastly is found in Bellsprout Tower.
Evolve a gastly that you can catch in the sprout tower
No Gastly cannot learn fly in Pokémon HeartGold.
Gastly are found in sprout tower.
Go to lavendar town and then enter Pokemon tower in there you can find a gastly.
Gastly evolves at LV. 25
you find gastly in the Burned Tower and the Sprout Tower
get a haunter by evolving gastly then trade to a friend and trade back and you have a gengar hope this info helps :-)
Ghastly evolves into Haunter at level 25. Then Haunter evolves by trading.
evolve gastly.
In the Pokemon tower or sprout tower.
sprout tower