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|Map description:||Though it was planned to be a subterranean city extending 69 floors underground, this project died in development.|
|Location:||Below Mauville City, accessed from Route 110|
|Location of New Mauville in Hoenn.|
|Pokémon world locations|
New Mauville (Japanese: ニューキンセツ New Kinsetsu) is a power plant located underneath Mauville City in Hoenn. Due to its unique location, the complex can only be reached by Surfing from Route 110 east under the Seaside Cycling Road to a small island east of the overhead path.
It was originally intended to be an underground city, before it was found that it served as a habitat for wild Pokémon.
In Generation VI, New Mauville has a special magnetic field that causes Magneton and Nosepass to evolve into Magnezone and Probopass, respectively, when leveled up here.
In Pokémon Ruby, Sapphire, and Emerald, Wattson stands at the intersection of Route 110 and Route 118 after the player earns the Balance Badge. He requests that the player shut down the generator in New Mauville as a safety precaution. To allow the player access to the underground plant, Wattson gives the player the Basement Key, which opens the door to New Mauville permanently. Wattson will remain in the center of Mauville City until the player returns, giving the player TM24 (Thunderbolt) as a reward after they shut off the generator. In Emerald, this also makes Wattson available for rematches, and allows other Gym Leaders’ teams to get stronger.
In Pokémon Omega Ruby and Alpha Sapphire, after defeating or capturing GroudonOR/KyogreAS, Wattson stands in front of the Square Tower in the outdoor area on 1F of Mauville City, where he will tell the player there is an issue with New Mauville, and requests that the player visit him in his Mauville Hills apartment (granting the player access to the Mauville Hills elevator at the same time). In his apartment, he requests that the player press the button on the computer at the back of the facility; he then takes a photo of the player character’s eyes and submits the picture to the New Mauville’s gate’s eye recognition software as authorized personnel, allowing the player to open the gate anytime. If the player visits Wattson in his Mauville Hills apartment after pressing the button, he rewards the player with TM24 (Thunderbolt).
In Ruby, Sapphire, and Emerald, the facility is a labyrinth of doors. There are green and blue doors, which only open when the corresponding…