REQUIREMENTS: You must have the HM Fly and be able to get to the Pokemon Factory (after deafeting the E4 Scott or something like that takes you there). You also must have the Southern Island cheat.
Go into the PF with your AR OFF
Get out really horrible pokemon (lvl 7 nincada for example) becuase you will lose them.
Choose OPEN LEVEL
Make SURE you choose a pokemon that COULD use FLY along with the other two.
AFTER you have chosen, turn your AR on quickly.
When you walk through the door, you will be transported to Southern Island. Teach the pokemon that can learn FLY FLY and fly away, back to the PF if you want.
Save after each of the sessions as a precaution.
ENJOY the Lvl 100s you have stolen from the Pokemon Factory!!!!