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Grand Spectrala Island (Japanese: マホラ本島 Mahora Main Island) is the third island Ash, Iris and Cilan visited during their travels through the Decolore Islands.
The island has one street, six houses and a dock. Only one person is known to reside the dock side, owning a restaurant there. The island does not seem to have any important landmarks; however, when the tide is sufficiently low, a path to a small islet is formed, where Giant Pokémon are said to live.
A pamphlet depicting the island; "Mahora Town Map" can be read on the front