You Can't Really See It Without The Modifier Cheat
no
First off all you have to do is have a other Pokemon game with baulbasaur then all you have to do is transfer him over not that hard !I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!I!
Besides the legendarys, Baulbasaur, Charizard, and Pikachu.
The only way you can see all the Pokemon on diamond is by going into the GTS and global trade different Pokemon.
you have to catch all of the pokemon in diamond or SEE all of the pokemon
A Pokemon
The Pokemon you see do not go in your pokedex.
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No, you cannot see every Pokémon in the National Dex in Pokémon Diamond however you can see every Pokémon in the regional Sinnoh Dex in Pokémon Diamond.
for diamond and pearl there are 150 Pokemon u need to see . in plat nium u neeed to see 210 Pokemon.
You see it in the Pokemon league The champion has it
You cannot see it in the wild in Pokemon Diamond; you have to transfer it from FireRed/LeafGreen.