NeoSpeedFreak
Trainer
This is easier than hacking the party.dat, and the game won't go slowly/glitchy. I would post images, but most of you don't speak spanish. *Don't forget to Save your progress and a copy of the original archive*
1. Open Notepad.
2. Go to Pokemon>Maps>poke folder, select all the archives and double-click a route. Example: Route 34.
3. Now opened, search the National Dex number of the Pokémon that you want to catch and replace the number that is after the zero to any line. Example: Scizor is 212 and Rattata 19, 212 will replace 19.
4. After the Pokémon number, appears a number from 1 to 100. That's percentage, this is a bit dangerous, you can change it, be sure that all percentages give in total 100. Example: Scizor has 70%, Abra, Ditto and Drowzee 10%, 70+10+10+10=100.
5. I don't know what does the next number, I think is about the time like hoothoot only appears at night. And the last 2 numbers are levels, like percentage change it if you want and they needs to be 1-100. Example: Scizor 17-17, Abra and Drowzee 10-11 and Ditto 10-12.
Good hunting!
Proof:
And if you didn't get the nature that you want (Example: You want an Adamant Phanphy, but you got a Mild one), here are the 4 most used natures (Edited in Party.dat):
3=Adamant
15=Modest
13=Jolly
10=Timid