A Pokedex is a trainers most important device . Whatever region your in it tells you every single Pokémon in that place ! In all Pokémon games you get a Pokedex .In diamond and pearl ash and dawn have a Pokedex . The only way to get a Pokedex is if you go on a adventure for professor oak that is how ash and dawn got theirs . If you press the button below it will take you to a online Pokedex from Pokémon's official website .