What do you do after you beat the elite four in Pokemon black?

Answer 1

Looker will visit your house and tell you that he needs your help to find the 7 (now 6) sages that have scattered across the region.

While you're finding them, you can now go to Black City and the two other cities that are on the other side of Nimbasa city, (They don't have gym leaders, but they do have lv. 60 + pokemon, so be careful.)

You can fight Cynthia in a beach house in Undella Town. She has the same team, only all are lv.75, with an exception of Garchomp who is lv.77,who can literally kick your *** (donkey...haha.) to next Thursday if you're below the 60's. (Trust me...I know.)

If you do beat Cynthia, something special will probably happen...or not.

Then if you're still playing, there's always the National Dex to complete and Second Round Elite Four to do. After that you pretty much beat the game.

or u can buy an action replay and hack ur game