Instructions
Equip the GS Ball.
Select Butterfree, Ghastly or another Pokemon who can use a sleep technique for your team.
Travel to Azalea town and drop the GS Ball by the torn shrine. Celibi will lunge at you.
Use your Pokemon to put Celibi to sleep. Attack him using "Tackle" and other weak physical techniques.
Throw an upgraded Pokeball, such as an Ultra Ball or Fast Ball, at Celibi once you have reduced his health points down to 10 percent.