>>19224575Don't listen to these guys. They know nothing about how to obtain a Wishappi.
Wishappi is the embryonic from of Jirachi, so you're going to have to breed a Jirachi with a Tentaquil. Tentaquil is the only Pokémon that Jirachi is able to breed with, and they're only obtainable in the grass patch next to the old woman on Kalos Route 37. When you go to the Day Care, make sure your Jirachi is holding a Berserk Gene!
Good luck!