yes i have completed the game. just vs every trainer you meet, and once you've beaten the elite 4 you've seen every Pokemon in sinnoh! Go down to prof. birch's house and you'll get the national dex which is a lot harder to complete (half of the Pokemon in there you cannot see in sinnoh)
See all 150 Pokemon in the Sinnoh Dex and talk to Professor Rowan.
you have to see all of the Pokemon and then you get the national pokedex from Prof. Rowen and Prof. Oak in Prof. rowen's lab after completeing the Sinnoh pokedex.
you need to see all the Pokemon in sinnoh region One Pokemon I found hard to see was the riolu, but you get it from Riley when its in a egg but basically you do nothing. Let it evolve.
yes.
No, you cannot see every Pokémon in the National Dex in Pokémon Diamond however you can see every Pokémon in the regional Sinnoh Dex in Pokémon Diamond.
You need to see all Pokemon in sinnoh
you have to see all the Pokemon in sinnoh.
you have to see all the Pokemon in sinnoh
You have to see all Pokemon Pokemon. But not the ones on nationaldex.
go and see all the Pokemon in the sinnoh dex
by going all over sinnoh and by trade
You have to see all the Pokemon in the Sinnoh Pokedex.
You have to see all of the Pokemon in the original pokedex.Then,go to Rowan in Sadgem Town.
See all 150 Sinnoh Pokemon
You have to see all the Pokemon in the sinnoh dex not including manaphy
He is in Sandgem Town, in the Pokemon Lab after you see all the Sinnoh Region Pokemon.
yes and to do so just see all the Pokemon in sinnoh to complete the sinnoh dex