You must catch every Pokemon, that's 493!! Good luck!
Oh yah, and it is imposible to catch, Deoxys, Jirachi, Arceus, Shamin, Daraki, Celebi and Mew with out going to a Nintendo event or hacking!
lier.you can use the Pokemon modifier cheat.if u want it look up "what is the best cheat for Pokemon diamond.i have it there.
To catch every Pokemon, you need action replay for the few last diamond legendaries. You will need Pokemon fire red/leaf green and emerald. Migrate them to Pokemon diamond. In Pokemon diamond, fill up your pokedex by catching Pokemon normally or with poke radar, or use gts. It will take a long time to catch all Pokemon
you would have to set loose some Pokemon in order to make room for other Pokemon.
You become an uber nerd;)
Do you have Giratina? Do you have a national pokedex? did you get Heatrans? If you have a national pokedex you can go to Celestic Town and go in the cave and observe the inscription. Cynthia says that it may not be the three lake Pokemon. maybe it's Dialga, Palkia, and Giratina. I dunno. I'm kinda at a loss, too... Just try to fill up your pokedex, i guess...
You can look up the pokedex for the hoenn region
Nothing. It just gives a great feeling that you did something.
the goal is to fill the pokedex,beat the elite four and level your guys up so you can get through the game
you have to fill up your pokedex
To research Pokemon, and fill up their Pokedex.
Yes you can. You just have to fill up your pokedex and talk to pr.Rowan.
what you do is go round and battle lots of different people and your pokedex will soon fill up that's what i did to fill up my and now i have completed the game.
Try to fill up the Pokedex.
To catch every Pokemon, you need action replay for the few last diamond legendaries. You will need Pokemon fire red/leaf green and emerald. Migrate them to Pokemon diamond. In Pokemon diamond, fill up your pokedex by catching Pokemon normally or with poke radar, or use gts. It will take a long time to catch all Pokemon
you can trade someone who has chickorita or migrate one from emerald if you got one in emerald if you completed the pokedex the profesor will let you choose one out of the three second generation beginner Pokemon
just use the Pokemon global trading system. if you have platinum pearl or diamond it is in jubelife city. and if you have heartgold or soulsilver it will be in goldenrod city.
Just catch the most Pokemon you can ;)
Once you have found every single pokemon in the sinnoh pokedex, go to professor rowan's lab in sandgem town. He will give the national dex. To catch pokemon to fill that up, you have to go to the island on the top right of your map. Which has TONS more pokemon. Hope this helped :D