There are several areas where Happiny live, but if you’re just starting the game and you haven’t made it to Mesagoza yet, try looking around the area in between your house and Mesagoza. Happiny will be spawning in that area.
More specifically, Happiny spawns in South Provice Area One, Two, Three, and Five, West Province Area One, and by the Pokémon League. Keep a keen eye out for the little pale pink Pokémon, since it can be very tiny and easy to miss if you’re not paying attention. Alternatively, you could breed any form of its evolution while holding the Luck Incense to get one.
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