A Traveler's Guide to the World of Pokémon/Hoenn/New Mauville

New Mauville is a power plant located underneath Mauville City in Hoenn in the fictional world of Pokémon. In the game, Wattson asks you to turn off the generator in New Mauville, and gives you a key to the "city". New Mauville is akin to the Power Plant in the Kanto, containing Voltorb and Magnemite. The plant also contains green and blue doors that only open when you step on the corresponding button color. Said buttons are found on the ground throughout the facility. If the generator is turned off and the player return to Mauville, Wattson gives them TM 24 (Thunderbolt) to thank them. Pokémon Voltorb Electrode Magnemite