Either cheating or trading or story events. I have heard a rumor after you get all 8 badges there is a extreamly small chance of running into any legendary Pokemon in the wild but that is just a rumor True or false i don't know.
it's used by cheats like using an action replay or a R4
skarmory is no legendary pokemon. it can breed and you can find it in the wild.
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
It is not a legendary Pokemon. Rather, it's a common Pokemon that you can easily find in the wild.
the wild Pokemon hack is either it is shiny or a wild lvl 100 or a legendary Pokemon ^^
arceus
you can't catch it because you already beaten the legendary