Instructions
Walk to the Safari Zone area of the region and walk through grass areas until you encounter a Pikachu pokemon.
Battle the Pikachu with grass or fire type pokemon, such as Charmander or Bulbasaur. Select a move and press the "A" button.
Select another attack move, such as cut or scratch, to get Pikachu's health to a red level. Select "Items" and "pokeball" to catch the wild Pikachu.
Press the "Start" button to bring up the main menu. Select the "Pokemon" option. Click "Pikachu" and select the "Switch" option.
Press the "Start" button again and select the "Items" option. The light ball will be available in your items list.