You don't see it. You have to hatch it from the Egg you received from Riley on Iron Mountain.
the girl on iron island has one.
Riolu is a Fighting type pokemon.
How does riolu learn aura sphere in pokemon diamond version?
Riolu
In Pokemon Diamond and Pearl the only way to get/see Riolu is in an egg. You can get the Riolu egg from Riley in Iron Island. You must have an empty space in your party then go through it with him and defeat a few Galatic Grunts. Then you will receive an egg, when it hatches you will have a Riolu. This is the only way to see/own it in the game. I hope this answers your question!
Riolu is 4 generation Pokemon. You can get egg only in Pokemon Diamond and Pearl
no but you get the riolu egg in iron island
happiny and riolu
hi Pokemon no.115 is riolu
Riolu (baby lucario)
the simble pokemon, unknown.
no