How do you catch all the Pokemon in Pokemon Diamond?

Answer 1

There is a secret in-game glitch that you can take advantage of if you have a strong starter Pokemon. The hack: (you can do this without action replay but action replay may help!)First, you need to defeat the elite four, 4 times. After that, fly home ad talk to your mom. She will give you EVERY Pokemon in the sinnoh pokedex that you do NOT have. She will deposit them DIRECTLY into your PC boxes. Start scanning from the 13th box or so. This will NOT fail and is NOT a scam. To complete the pokedex, (seeing every single sinnoh Pokemon), you will need to battle EVERY single trainer. It is indeed a hassle, but it does pay off. This only took me about 2 and a half weeks. only about 67:29 on the time log in screen. Indeed, many people donot want to waste time battling all the trainers but it seriously pays off.

Answer 2

You must have Pokemon Emerald, Pokemon Ruby, Pokemon Sapphire, money, skill and knowledge. You also need friends help to trade and get the Pokedex full. After that, just ask to trade back. Also try your best to find all of the Pokemon in the version you have. Try and concentrate on finishing the Pokedex.