there are a few aswers
1:how to get rigigagas beat Pokemon league finnish pokedex and have all the rigas
then go to snow point temple they will let you in then get to rigigigas youre self
PS has a strong atack but the abilate is to half its defence and speed for a cople of
terns.
2:garatina to get him you half two beat the elite4 then there will be a new area
TM needed:rock climb,defog and if you want rock smash
the new area is basickly a maze after you find three pillers there will be four dores
go thro the top one and you will battle him after you catch him or defet him go bck to
find a rare bone and somtimes stardust
3:dialga first legendary you can get.Get thero that big cave you will battle team
galactic you will battle dialga after you catch or defet dialga go farther in back
of dialga you will find an item it is somthing he youses
the legendary Pokemon in diamond and pearl are dialga and palkia.
No, a Bidoof cannot evolve into any Legendary Pokémon in Diamond.
Heatran
a lot of legendary Pokemon
Dialga
you cant unfourtanately
arceus
you can't catch it because you already beaten the legendary
no
you can't unless you have AR
Empoleon is not a legendary Pokemon. It is the final evolution of Piplup, one of the starter Pokemon in Pokemon Diamond, Pearl, and Platinum.
That would have to be Dialga.