Things You'll Need
Instructions
Solo Tips
Evolve your Pokemon by leveling them up. Every time you evolve a Pokemon, the new, evolved form will be added to the pokedex.
Explore every inch of the world map. Some Pokemon are confined to very small regions in the game and you won't find them anywhere else.
Wait for specific times of day. Certain Pokemon -- such as Fearow and Arbok -- have a greater chance of appearing when the Nintendo's DS internal clock is set to either morning, day, or night.
Battle every Pokemon trainer you meet. Each time you encounter a new Pokemon in battle, even if you don't catch it, it will be added to your pokedex.
Hatch Pokemon eggs to receive new species. Obtain Pokemon eggs by talking to characters such as the old man outside the Day Care Center, or by breeding a male and female Pokemon together.
Use Stones on different Pokemon, which will sometimes evolve them to a new form. For example, use a Thunder Stone on Pikachu and it will evolve to Raichu. Use a Water Stone on a Poliwhirl to get a Poliwrath. Use a Fire Stone on Growlithe to get Arcanine.
Trade Pokemon while holding different items. For example, if you trade a Porygon2 that's holding a Dubious Disc, it will evolve into a Porygon-Z.
Teach certain moves to different Pokemon before leveling them up. For example, level up a Tangela that has learned the move "AncientPower," which it receives at level 33, and it will evolve into a Tangrowth.
Friends and Other Games
Migrate Pokemon from "Pokemon FireRed" and "LeafGreen" for the Game Boy Advance by inserting the cartridge into the Nintendo DS's Game Boy Advance cartridge slot, opening "Diamond," selecting "migrate" and choosing which Pokemon to migrate. This is the only way to obtain certain Pokemon that aren't naturally found in "Pokemon Diamond," such as Bulbasaur.
Explore the game while a copy of "Pokemon FireRed" or "Pokemon LeafGreen" is in the Game Boy Advance slot of the Nintendo DS to discover new Pokemon. For exmaple, search Route 204 with "Pokemon FireRed" to find Caterpie, and search the same area with "Pokemon LeafGreen" to find Weedle.
Connect your Nintendo DS wirelessly with a friend who has a copy of "Pokemon Pearl" by opening the Pal Pad from the Items menu, registering Friend Codes, and selecting Single Battle on both systems. Make sure your friend selects one of the 20 Pokemon that are unique to "Pokemon Pearl" for you to battle against. Repeat the process until all 20 Pokemon are added to your pokedex.
Trade certain Pokemon to friends who have a copy of "Pokemon Diamond" or "Pokemon Pearl." Sometimes the action will trigger an evolution after the trade is completed. Try this with a Kadabra and it will evolve to an Alakazam. Trade a Machoke and it will evolve to a Machamp and trade a Graveler to evolve it into a Goldem.
Complete the "Recover the Precious Egg" mission in the Nintendo DS game "Pokemon Ranger," and transfer the egg to "Pokemon Diamond" while the game is running on a second Nintendo DS system. While in "Pokemon Diamond," visit the PokeMart and receive a special egg that will hatch into Manaphy.