You can go on Pokemon websites and check out all the 493 Pokemon or you can get the action replay DS for you DS and get the 100% Pokedex complete code to see them all on your game.(IF YOU HAVE IT.)
256 pokemon. But all together 493.
there are actually 493 Pokemon and you see them all by just playing through the game and searching in all the different routes, also you will need a friend with pearl to see them all, it will take a very long time though hope that helps
it'z a pokedex that can show you 493 Pokemon if you see them
By running around in the tall grasses, inside the caves, surfing and fishing in water, trading Pokemon and fighting other trainers. But to complete the Pokedex and get the star on your Trainer Card you have to catch all 493 Pokemon.
You need to catch all of them not just see them (not including event pokemon)
150 (and Manaphy, but you don't need to see or get it) in the Sinnoh Dex, and 493 in the National Dex. There should be 151 Pokemon in Pokemon Diamond.
493 is only how many the pokedex says there are. But Pokemon like shellos there is two types but the pokedex only counts it as one. Arceus evolves into different types if you use a certain type of stone and the pokedex still only counts all those combinations as one. If you want to see it for yourself check out this website: http://www.serebii.net/diamondpearl/newpokes.shtml
technically there are 493 not including black and white but with black and white there are about 649 different Pokemon. now i would tell you what Pokemon they are but there are too many to name you can see what Pokemon they are by searching Pokemon Bulbapedia on Google or on any other search sites
You can see all the Pokemon
You have to see the 150 Pokemon in the Sinnoh region to get the National Pokedex in Pokemon Pearl. #151, Manaphy, is obviously not included. You also may be missing some Pokemon but havnt been to the Pokemon league there are several Pokemon there that are added in so check it out
The only way you can see all the Pokemon on diamond is by going into the GTS and global trade different Pokemon.
You can see all kind of Pokemon, except legendary Pokemon.