After you defeat Gary you become the elite 4 champion but Gary will still be there. You will enter the hall of fame. During wirerless play if you beat the elite 4 and challenge your friends to it you will be the champion instead of Gary.
After defeating the Pokemon League, Lance (the 4th Elite Four trainer), will tell you that you would have been the Champion but someone had beaten you to it. A trainer who is your Rival; Blue (Gary according to his anime name) had beaten Lance before you came and therefore became the Champion now you must defeat him to take his title however once you beat Blue, Professor Oak will come to congratulate you and he will record your Pokemon in the Pokemon Hall of Fame which you will be able to view via the PC at your home or at any of the Pokemon Center, it will keep a record of the teams you have used to defeat the Elite 4 and Blue and then the ending credits will roll and then you will be put back in your house in Pallet Town and since you've beaten the primary objective of the game your next objective is to catch all 150 Pokemon and once you have accomplished that goal you can elect to go to the Celadon Mansion and receive a diploma from one of the Game Freak employees.
you become the champion and now you can go to the battle zone
he spontainiosly combusts P.S don't do it P.S.S I'm homer Simpson
You go to the battle frontier F BFGYH RF<:ojnaf hoped i helped ;)
Nothing significant happens if you beat the Elite 4 three times in Pokemon Diamond, unless you include acquiring huge amounts of money and leveling up your Pokemon a very good amount.
you get laid
nothing
uh.... why would you beat it 40 times in the first place you freak!!!
you should go look for the legendaries
yes, you beat them ten times
Absolutely Nothing.
Nothing significant happens if you beat the Elite 4 three times in Pokemon Diamond, unless you include acquiring huge amounts of money and leveling up your Pokemon a very good amount.
Nothing. Don't waste your time.
Then you beat them:)
After 20 wins, your rival's Pokemon level up.
you get laid
Then you beat them 100 times and win :)
I think you have to beat the Pokemon Elite five times.
finish the nation pokedex
nothing
you get him after you beat the Elite Four 1,000 times. Trust me, it took me 1 year to beat the Elite Four just 500 times.