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Route 106 is, more water, and more trainers.

• Swimmer Nicole
  • Wailmer (lvl. 27)
• Swimmer Douglas
  • Tentacool (lvl. 26)
  • Tentacool (lvl. 26)

As soon as you can, get to the sandy beach to the south, because after Douglas there isn't anything interesting in the water. There is, however, a Protein on the beach.

Pokémon found (water)

Sapphire	Encounter Rate	Ruby	Encounter Rate
		Magikarp
		Tentacool
		Wingull
		Pelipper
		Wailmer