Just catch the most Pokemon you can ;)
You have to battle every single trainer if not true improve answer
you have to fill up your pokedex
Yes you can. You just have to fill up your pokedex and talk to pr.Rowan.
fill up sinnoh pokedex to national pokedex.
Without an Action Replay, there is no easy way to fill the National Pokedex.
first of all you dont need to fill up your OWN pokedex to get national pokedex. you could get the national pokedex after you beat the new champion N and you need to beat ghestis. after that go back to your own town and the pofesser's father will give u a national pokedex. And for filling up your pokedex go around the world and search for evloesion of every pokemon or find some pokemon and evloe it or something like that.
First you bet all of the gym leaders and the elite 4, then you fill up the Sinnoh pokedeck. After that you talk to Professior Rowan, and get the national pokedex. Then you bet the new team glatic master, and fill up the national pokedex
Fill up your Sinnoh pokedex. Here's something that will help you: Rotom.
no they don't add Pokemon into your pokedex there
You've beaten the game. I guess just fill up your pokedex and truly check them all.
you have to see all of the Pokemon and then you get the national pokedex from Prof. Birch and Prof. Oak in Prof. Birch's lab after completeing the Sinnoh pokedex.
first,you have to fill up national pokedex second,go to pacifilog town third,talk to the girl on near in Pokemon center fourth,she will have you the ticket to the charmander,squirtle and bulbasaur islands :p