Unlimited Rare candies and Luxury balls!!!
Go to Five island then surf going to the Water Labyrinth and go to Resort Gorgeous and go to Selphy's house (you must help Selphy in Lost cave if you haven't help her) then after you help her, then she wishes to see a Pokemon, if you bring the Pokemon that she wished to see it... She will you Luxury balls, Rare candy, Nugget and etc etc...
Theres loads more info this game, right here, with some cheats and tips, answers and Pokemon LeafGreen walkthrough.
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