Things You'll Need
Instructions
Defeat the Elite Four and talk to Professor Rowan in Sandgem Town to receive the National Pokedex.
Insert a Game Boy Advance "Pokemon" version with a captured Suicune into the GBA cartridge slot of your Nintendo DS.
Press "Start" to bring up the in-game menu and select "Save." Save your game and restart your Nintendo DS system.
Press "Start" at the Nintendo DS menu to reload your "Pokemon Pearl" game.
Select "Migrate from (GBA game)" on the title screen menu and press "Yes" to confirm. Use the directional keypad to navigate through six Pokemon you wish to transfer and press "A" to confirm.
Travel to Route 221 and enter the Pal Park. The rangers will give you Park Balls, which guarantee the capture of any Pokemon that you encounter in the park.
Walk around the enclosed areas within the Pal Park to encounter random wild Pokemon that were migrated over from your Game Boy Advance version. When you encounter a wild Pokemon, you must capture it with a Park Ball to continue.
Explore and walk through various areas in the Pal Park to encounter Suicune. Throw a Park Ball to capture it.