It's a Pokemon event. You will have to wait.
Its either through an event or through action replay
there are to ways to get darkari in Pokemon diamond and pearl 1) get an EVENT PASS from certain events then go to canclave city and sleep a night in the locked house (note you cannot get in without the EVENT PASS) you will be troubled by darkari in your dreams when you wake up in the morning you will be able to go to the island where darkari lives he is level 40 so be prepared 2) go to the island where you find cresellia then use an action replay to activate the "walk anywhere" cheat walk east until you find an island there you will find darkari i hope this helps you like it did me
Darkari
you need action replay and find a code on youtube
You need a members pass/card to get into the hotel in the same town, then you'll be at the island after a bit of dialogue (You can only get a members pass/card from Pokemon events or AR).
special mission.
You can find Pidey in a Pokemon Outbreak in Pokemon Diamond
hi i ave a darkrai wat wud u be willing to trade 4 it
Darkrai cannot be captured in SoulSilver. You have to transfer it from Diamond, Pearl, or Platinum. On those games, it is only obtained via an event.
When the salior asks for you to help his son, help him, and wake him up. The boy mutters "Dark is watching me", reffering to Darkari. To open the locked hotel, get the Memdership Card (event). Once inside, the message "Welcome to the hotel. Ha ha ha!" (or something close) is what Darkari tells you. Approch Darkari and save the game. You screw this up if you K.O. Darkari. Other ways are: A: Go to a Nintendo Event or B: Trade for it.
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.