No only in ruby and sapphire and emerald just trade one from those games to leafgreen and now you have it.
Bagon is a Dragon type pokemon.
All Hoenn Pokemon (bagon is just one of them) cannot be obtained in either Firered or Leafgreen you will need one of the versions that resides within the Hoenn region those versions are: Ruby, Sapphire and Emerald.
Sorry but there isn't a trainer with a bagon in platinum.
trade from ruby/Sapphire/emerald bagon is a newer Pokemon leaf green focuses on the original 150 or catch at lost cave but get alot of max repels it is a glitch but it to work always hack yer game to acsess hoen region dex stuff.
You can find bagon in white forest
Bagon evolves into Shelgon at Lv.30
Bagon is only available in Pokemon pearl. You can however catch a Larvatar instead of a bagon. you can trade one for a Bagon because another pearl player will want one.
Bagon is only available in Pokemon Pearl, but you can obtian it in Pokemon diamond by trading someone who has pearl
you lvl it up to lvl30 bagon evolves to shellgon
Bagon evolves in to Shelgon at level 30.
Yes you can trade leafgreen version Pokemon to another leafgreen version.