you can if you have action replay or any game device but if you don't you have to get the national pokedex to get darkria
You can't get it without first getting the National Pokedex. When you get the National Pokedex, go to Canalave City and go to the house next to the sailor. Then he'll be in bed. First talk to him, then his mother.
You must have the National PokeDex to capture Heatran.
you have to trade them from a game that has the national dex.
the kanto pokedex YES national not sure but i think you have to trade from ruby or sapphire or something
=Its not possible but getting aceus is without action replay=
You can't.
no
It depends on the Pokemon you're trying to evolve. While some Pokemon can evolve without any problems due to being in the regional Pokedex, other Pokemon (Golbat, for instance) won't evolve without the National Pokedex. Note that this is only the case in FireRed and LeafGreen - in later games, Pokemon not in the regional Pokedex will evolve, but won't be recorded until you get the National Pokedex.
you need a cheat for it.
you cant
you can't
You can't. You have to get NationalDex and then talk to Bebe. She will give you a free eevee, though I think it only works once