yes you have to do the Pokemon league
You can only get bagon in pearl. (and other GBA games) But you can catch lavitar on route 207. If you use the poke rader. They are kind of rare.
Beat the elite four and then go to Rowan then he will give you the poke' rader
Get the national poke dex and talk to profeser rowanTo do that you have to see every Pokemon in the small poke dex you will get the Poke rader! :]
you need to use the poke rader and find a girl snorunt and give it a dawn stone and it will evolve in to froslass
Route 210 (fog) you have to use the poke rader to find it.
You can only catch bagon in pearl. But you can catch larvitar, route 207, you have to use the poke rader. If you had pearl you would find bagon on route 210 (fog) with the poke rader.
No you don`t have to use the poke-radar to catch lavitar.
Chain 40 of the same Pokemon
most important, you have to beat the elite four. Then go to professor Rowan's lab, there you will find professor Oak and he will give you a poke rader.hope this helped!
There is no poke radar in emerald. Only in diamond and pearl and platinium
you have to use a poke rader on route208
you complete the pokedex for prf. rown and then he gives it to you. :)