As an expert in Pokémon game mechanics, I can guide you through the process of accessing New Mauville in Pokémon Emerald. New Mauville is a special area that can only be accessed after you've defeated the Elite Four and become the Pokémon Champion. Here's how you can get there:


1. Post-Game Progression: After becoming the Champion, you'll need to continue the post-game story by visiting Professor Birch in Littleroot Town to receive the Devon Goods Key.


2. Devon Corporation: Travel to Mauville City and head to the Devon Corporation building, which is located in the north-east part of the city.


3. Key Item: Use the Devon Goods Key on the employee in the Devon Corporation to receive HM05 - Flash.


4. Accessing the Cave: Once you have HM05, go to the north of Mauville City where there's a cave entrance that was previously blocked by a worker. Use Flash to move the boulders and clear the path.


5. Navigating the Cave: Enter the cave and navigate through it. You'll need to use Flash to progress, as some areas are only accessible with this HM.


6. Arrival at New Mauville: After navigating through the cave, you'll emerge in a new area known as New Mauville. This area is home to different Pokémon and trainers compared to the regular Mauville Cave.

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New Mauville is a small facility in central Hoenn. It can be reached by surfing along the northeast side of Route 110. The door inside the building will not open until you get access from Wattson in Mauville Hills. This will happen after dealing with the Ancient Pokemon in the Cave of Origin.read more >>