You will not see Cyrus after you get Palkia.
The only way to see Palkia in Pokémon Diamond is to use WiFi. Otherwise, you can't.
You can not see it
You cannot battle Palkia in Diamond however you can go talk to Cynthia's Grandma in Celestic Town in order to see it.
Palkia lives in Spacial Rift,but you must complete the Nightmare to see him.
you will need to have one of your friends trade you a palkia, and then have you trade it back. You don't even need to exit the trade, it will automatically add Palkia to your dex.
Try looking for a Golden mask which boosts recruit rate. Complete deep spacial rift where you see palkia hold the golden mask then kill palkia Palkia SHOULD want to join your team if not try again
yes.
If you want to get Pulkia(Palkia) go see the elderly woman in Celestic Town, talk to her and she'll show you a picture of Palkia. After that you should be able to see Palkia in the GTS and be able to trade for it. Or go buy Pokemon Pearl and trade from your Pearl version.
After beating Cynthia, go to Celestic Town. In one house, there's a book with a picture of Palkia in it. That will count toward your Pokedex.
If you have arceus, you go to the ruins of alph and you talk to a man and he will be suprised that you have arceus and then you will see Cynthia and she will tell you to choose Palkia, Dialga, or Giratina
You can't see palkia on Pokemon diamond unless you trade. However, it will be added in the pokedex after you've seen dialga and visited the elder of Celestic toen. She will show you a picture of palkia.