you go to celadon city into the game corner and there is someone from team rocket and after you get past him you pull the poster you go into the tr base. after you win you get the silph scope and you can fight the ghost.
Dark attacks. I suggest something common such as bite which a lot of the early pokemon can learn
beat the Pokemon league
Catch all the Pokemon!
beat the elite four and the champion.
beat the rockets in celadon (search the poster) and giovani will give you the silph scope, go to the Pokemon tower and use it
You can beat a ghost type with another ghost type (Like Haunter)
Dark type can beat ghost.
nuke em
shadow ball is the strongest ghost TM
they are always the same Pokemon :):):):):)
after you beat the fire gym then walk out and your rival will give it to you.
You cannot catch the ghost in the Pokemon Tower until you reveal what it really is.