you cant.
you can only get registeel from Pokemon sapphire, emerald, and ruby.
you can get regigigas, you just need to have registeal regirock and regiice in your party to catch it, it is in the temple a snowpoint city, botom floor!!!!
Trade it from Pokemon Emerald/Ruby/Sapphire
You can find Pidey in a Pokemon Outbreak in Pokemon Diamond
you have to get a movie regigigas and then you have to go and get registeal regiice and regirock then you go to the sacred place in snowpoint city go through the maze and at the end you (you must have the regies in your party)your can get regigigas at level 1
where do i find a totodile in Pokemon diamond/pearl on nintendods
You can not find or get manaphy on Pokemon diamond but you can by hacking, trading or... if you have Pokemon ranger you have to complete the manaphy mission and then you can put it onto diamond.
there are three that you can CATCH in pokemon emerald its Groudon, Kyogre, and rayquaza regice registeal regirock litos lotias
You can't find a Ho-ho in Pokemon Diamond. You have to migrate.
To get a Manaphy in Pokemon Diamond you have to get Pokemon ranger and defeat it and you have to trade it to Pokemon Diamond,Platinum or Pearl.
its not a Pokemon
Not really that rare... in Pokemon Diamond you can find Sunkerns on Route 204
you have to catch all of the pokemon in diamond or SEE all of the pokemon