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It is not necessary that you explore the upcoming routes but it helps you with experience. In addition, you can capture some Pokémon. Route 129 does not hold any surprises. There are a few swimming trainers.

• Triathlete Allison
  • Wingull (lvl. 25)
  • Wingull (lvl. 25)
  • Wingull (lvl. 25)
  • Staryu (lvl. 33)
• Swimmer Reed
  • Carvnha (lvl. 32)
  • Sharpedo (lvl. 32)
  • Spheal (lvl. 32)
  • Carvanha (lvl. 32)
• Swimmer Tisha
  • Chinchou (lvl. 33)
  • Luvdisc (lvl. 33)
  • Pelipper (lvl. 33)
• Triathlete Chase
  • Wingull (lvl. 27)
  • Staryu (lvl. 35)

[edit] Pokémon found

• Tentacool
• Wailmer
• Wingull
• Pelipper
• Magikarp