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Pokémon: Let's Go, Pikachu! & Let's Go, Eevee!

Route 20 (Part 1)

Vincent Lau

Careful you don’t fall off. We don’t think your partner can swim to save you.

Wild Pokémon

Pokémon Type Location Chance (%)
Gyarados Water/Flying Water’s surface 5
Tentacruel Water/Poison Water’s surface 5
Tentacool Water/Poison Water’s surface 45
Magikarp Water Water’s surface 45
Lapras Water/Ice Water’s surface Rare spawn

This route leads directly to Cinnabar Island, but to get there, you’ll need to cross through Seafoam Islands in the middle. As soon as you come from Route 19, there’s a male swimmer towards the north, right near the rocks that form the boundary.

Swimmer Douglas

Pokémon Level Type
Gyarados 42 Water/Flying

Gyarados is an evolved Magikarp and a threatening Pokémon. It’s weak to Rock and exceptionally weak to Electric. Rock-types are weak to Water though, so be careful. It can attack using Waterfall for STAB, Crunch to hurt Psychics and Ghosts, and Dragon Pulse for other purposes.

Next, there’s another male swimmer a short distance west, about halfway along the route.

Swimmer Darrin

Pokémon Level Type
Golduck 44 Water
Gyarados 44 Water/Flying

Darrin’s Golduck knows Surf and Psybeam. It can also use Disable to stop you using a previous move. Meanwhile his Gyarados has Waterfall, Crunch and Outrage–the latter is a powerful Dragon move that makes the user confused after a while. Field an Electric-type if possible.

After that, keep swimming west. There won’t be much to see for a while. But eventually, there should be a female swimmer near the north side of the route.

Beauty Shirley

Pokémon Level Type
Wartortle 41 Water
Starmie 41 Water/Psychic

Wartortle is the middle evolution of Squirtle. This one can use STAB Bubble Beam, plus Protect to waste your moves. Next up, Starmie can use Psywave to deal from between 20 to 61 damage. For reference, it’s weak to Grass, Electric, Bug, Ghost and Dark.

From there, you’ll reach Seafoam Islands if you continue west for just a little longer. Upon landing, head over to the west side of the island. You should reach a cave entrance.

If you think you’re ready, head on inside the cave.

Guide Information

  • Publisher
    Pokemon Company International
  • Platforms
  • Genre
  • Guide Release
    23 November 2018
  • Last Updated
    19 December 2020
    Version History
  • Guide Author
    Vincent Lau

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Welcome to our strategy guide for Pokemon: Let’s Go!

  • A complete walkthrough with strategies to defeat all the Kanto Gym Leaders and conquer the Pokémon League.
  • Encounter tables for all the wild Pokémon, including the rare Pokémon with undisclosed habitats in the Pokédex.
  • Explanations of all the gameplay mechanics for both beginner trainers and Pokémon Masters.
  • Where to find all the Master Trainers and hidden battles after beating the game.
  • A handy mini-Pokédex containing the key details for all 153 obtainable Pokémon and where to find them.

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