All Pokemon in Pokemon Diamond

Answer 1

this is not true until you get the national pokedex... wl actually you cannot catch all the Pokemon but you can download or "migrate" as Nintendo say it onto diamond just by pluging in either pkmn fire red, leaf green, emerald, Sapphire or ruby using pal park.

you also sometimes have to trade with people on another ds console, probably if they had pearl it would be best coz if you want palkia it is not available on diamod and you have to get it from pearl. the best way to get giratina also is to trade him from platinum so you don't need to get national dex yet to unlock wayward passage and wayward cave. i am a real nerd at Pokemon lol :)