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A building on Monsu Island
Monsu Island (Japanese: モンス島 Mons Island) is an anime-only location in Hoenn. It is located between Lilycove City and Mossdeep City.
It made its only appearance in Gaining Groudon, in which Ash and his friends unknowingly boarded a ship that belonged to Team Magma. Monsu Island is the location of the bases of both Team Magma and Team Aqua.
Pokémon seen at Monsu Island