I've hered If you go to the game desiner he will give you somthing, on Sapphire if you get all the honan Pokemon and go to prefesor oke you can get another starter Pokemon (202 Pokemon or 200) in honan ,on dimand and perl after getting all 493 Pokemon you get an up-Grade (But you proberly have that oredy)you can get a poster or both(I don't no much about dimand and pearl I think these are rumers so just bare with me ok
you have beaten the game and that's it.
You get a diploma and a gold trainer card.
I dont know what happen in diamond, but in platinum you can catch ! and ? unowns.
"I want to be the very best, Like no one ever was, To catch them is my real test, To train them is my cause..." I believe that sums up what you do after beating red
A diploma is something professor oak gives you when u catch all the Pokemon in fire red
the fun of having them i guess
you have beaten the game and that's it.
you can get certificate from the gamemakers by going to the celdon mansion
You go to professor britch and he gives the fire red starters
nothing happens
Nothing.
nothing
You would get a depoma for getting all the Pokemon
u win the grand monologue and all your Pokemon go to lvl 99. actually i think professor oak gives u a diploma that's what happens in all the other games.
nothing happens you just do it again i think.
A pat on the back
catch em all!