Go to the trophy garden in the Pokemon mansion and catch two pikachus; make sure one of them has a light ball when you catch them. Then go to Solaceon town and give the pikachus to the day care lady. Talk to the man outside the day care center and he will give you an egg. When the egg cracks open a pichu with volt tackle comes out. Note: If you want a female pichu give the light ball to the male and if you want a male give it to the female.
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