If you defeat the Elite Four Twice, you will have the opportunity to battle the Champion, Alder. He has mostly Level 72 to Level 75 Pokemon.
nothing
You just get legendary Pokemon I guess
route 7 after beating the elite 4
No, it does not. you can challenge the Elite four as much as you like.
You can continue to challenge the Elite Four for money and Exp. Also you can get additional badges (stickers). Hall of Fame Sticker #1 Beat The Elite Four One Time Hall of Fame Sticker #2 Beat The Elite Four Fourty Times Hall of Fame Sticker #3 Beat The Elite Four One Hundred Times Hall of Fame Sticker #4 Beat The Elite Four Two Hundred Times
You need to beat the elite four before you can get Zekrom.
Then you beat them:)
You beat the elite 4 and N
Then you beat them 100 times and win :)
the credits start
you get laid
you have to beat the elite four twice