Pretty Petal Flower Shop: Cheri, Chesto, Pecha, Rawst, Aspear, Leppa, Oran, Persim
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After losing a contest: Lum
Pokemon Contest Awards (normal): Cheri, Chesto, Pecha, Rawst, Aspear, Leppa, Oran, Persim
Pokemon Contest Awards (super): Sitrus, Figy, Wiki, Mago, Aguav, Iapapa, Razz, Bluk, Nanab, Wepear, Pinap
Pokemon Contest Awards (hyper): Pomeg, Kelpsy, Qualot, Hondew, Grepa, Tamato, Cornn, Magost, Rabuta, Nomel, Spelon, Pamtre, Watmel, Durin, Belue
Pokemon Contest Awards (master): Occa, Passho, Wacan, Rindo, Yache, Chople, Kebia, Shuca, Coba, Payapa, Tanga, Charti, Kasib, Haban, Colbur, Barbiri, Chilan, Roseli
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Inver, Mauville City: Oran, Sitrus, Occa, Passho, Wacan, Rindo, Yache, Chople, Kebia, Shuca, Coba, Payapa, Tanga, Charti, Kasib, Haban, Colbur, Barbiri, Chilan, Roseli
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Mauville Food Court, Villager Sub Combo: Figy, Wiki, Mago, Aguav, Iapapa
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Route 111: Razz
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Secret Base, if Secret Pal can gather berries: Cheri, Chesto, Pecha, Rawst, Aspear, Leppa, Oran, Persim, Lum, Sitrus, Liechi, Ganlon, Salac, Petaya, Apicot, Kee, Maranga
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Route 114: Razz, Bluk, Nanab, Wepear, Pinap
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Route 120: Figy, Wiki, Mago, Aguav, Iapapa
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Berry Master: Pomeg, Kelpsy, Qualot, Hondew, Grepa, Tamato, Cornn, Magost, Rabuta, Nomel
Berry Master's wife: Cheri, Chesto, Pecha, Rawst, Aspear, Leppa, Oran, Persim, Lum, Sitrus
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Lilycove City: Cheri, Chesto, Pecha, Rawst, Aspear, Leppa, Oran, Persim, Lum, Sitrus
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Kiri, Sootopolis City: Figy, Wiki, Mago, Aguav, Iapapa, Razz, Pomeg, Kelpsy, Qualot, Hondew, Grepa, Tamato, Cornn, Magost, Rabuta, Nomel
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I couldn't find a way to get unlimited of them: Lansat, Starf, Enigma, Micle, Custap, Jaboca, Rowap