Good question. Once you beat the champion who happens to be your rival you must catch at least 60 Pokemon on your pokedex. You also have to get all of the gifts from professor oak's aids. You get HM flash for 10 Pokemon, an everstone for 20 Pokemon, an item finder for 30 or 40 Pokemon, and an EXP share for 50 Pokemon. Once you collect 60 Pokemon and get all of the gifts from professor oak's aids go to his lab and talk to him. The I think your rival will come in and professor oak will say that new Pokemon have been apearing recently. Next professor oak will give you a national pokedex. After that if I remember correctly you must talk to Celio, Bill's friend. He will give you a rainbow pass which allows you to go to 4, 5, 6, and 7 island! Many new Pokemon live there and wait for you to catch. Celio will send you on a task to find a ruby and a sappire ( the machine's power source ) and allow you to go to 4, 5, 6, and 7 island. Once you finish your task finding the ruby and sappire and return them to Celio, not only will you be able to traded with Ruby, Sappire, and Emerald version, but the elite four will rematch you even stronger. ( an example would be that both of Bruno's onix evolved into steelix ) I hope I helped you!!!
beat the Pokemon league
nuke em
defeat the Elite Four at the indigo league
u go to the place
no she is not
Pokemon league
Talk to oak after you beat the pokemon league.
it is in victory road when your going to the Pokemon league
Beat the pokemon league.
The elite four will be in the Pokemon league.
After you beat the Pokemon league.
you need to do the Pokemon league