NOTHING! They think you need to get a life and they tell you off. true story. :D
you complete the national pokedex
pokedex or National
You get a Diploma from the game designer from inside the game (Celadon city in one of the buildings), you can print out the diploma if you have a game boy color printer and professor Oak says your pokedex is complete. That is all to it. Nothing special.
You get the national pokedex and a jhoto starter.
Tell me!
Do the aftergame stuff
Congrats you receive a diploma from the game designer at the celadon mansion, you receive a gold trainer card and show your dex to oak and he will... roar at you.
Complete the Unova pokedex (after that coplete the national pokedex)
im pretty sure u get a national pokedex (national dex)
Nothing juniper is just proud of you
there is not one
jrkmexph