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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, arriving there in The Island of Illusions!.
The island has one street, six houses, and a dock. Only one person is known to reside the dock side, a large man resembling a Snorlax who owns a restaurant. The island does not seem to have any important landmarks; however, when the tide is sufficiently low, a path to a nearby small islet is formed, where Giant Pokémon are said to live. Grand Spectrala Islet consists of mostly forest, as well as a rundown Pokémon Center.
During the events of The Island of Illusions!, Ash and his friends met the restaurant owner on the dock, who told them of the Giant Pokémon living on the nearby islet. Curious, the group ventures over to the islet to investigate. They came across a giant Heatmor, who chased them to the edge of a cliff before vanishing. While being chased, Axew was hit with Stun Spore from an also-fleeing Foongus. After the group's encounter with the giant Heatmor, they started to search for someone who could help Axew, and came across the Pokémon Center. Desperate, they went inside and found that there was a Nurse Joy and Audino there to help them. While they seemed rather odd, Nurse Joy and Audino were able to make a medicine out of Berries for Axew, which cured the Pokémon instantly.
Suddenly, an older Nurse Joy entered the facility and told the Joy behind the desk to stop all operations effective immediately, as the Center was apparently being illegally operated. Instead of apologizing, the Center's Nurse Joy reveals that it was a Zoroark that used to spend time with the real Nurse Joy at the facility, before the Center was shut down due to the dwindling amount of Pokémon Trainers needing assistance. The older Joy, who turned out to be the same Nurse Joy who used to work at the Center, apologized for leaving and decides that she would stay with Zoroark and turn the old Center into a special Pokémon Center for wild Pokémon.
A pamphlet depicting the island; "Mahora Town Map" can be read on the front