From Mauville City, go south, you'll meet the Fisherman. Surf and keep to east. Then, you reach the New Mauville.
Go south until you are below and out of Mauville City, and Surf in the water until you find a cave: That;s New Mauville.
In Pokemon Sapphire when the player defeats Gym Leader Norman in Petalburg City, Wattson, the Gym Leader of Mauville City can be found at the intersection of Route 110 and Route 118. Upon talking to him, he will give the player the Basement Key to access New Mauville City.
I would say the one on the way to de-activate the generator at new mauville near the cycling rode in Ruby, Sapphire, and Emerald.
New Mauville MissionMr. Wattson wants you to turn off the big machine at the end of New Mauville by pressing a red button. The cave's full of Electric-type Pokemon and no Trainers.
The cave Wattson, the Mauville City Gym Leader, tells you to venture inside is New Mauville. He wants you to turn off the generator inside New Mauville. It appears to be acting up and causing problems for people in Mauville City. Inside New Mauville are various items and switches that allow you to navigate through New Mauville and reach the generator. There is also wild Pokemon in the power plant like Magnemite, Voltorb (Three fake items are Voltorb), Electrode, and Magneton. To reach New Mauville you must head south of Mauville City and use Surf in the lake located in Route 110. Surf below Cycling Road and you will see a cave entrance. That is New Mauville. To enter the power plant, it requires the Basement Key (Which Wattson gives to you after taking the request). Hope this helps.
Go south until you are below and out of Mauville City, and Surf in the water until you find a cave: That;s New Mauville.
In Pokemon Sapphire when the player defeats Gym Leader Norman in Petalburg City, Wattson, the Gym Leader of Mauville City can be found at the intersection of Route 110 and Route 118. Upon talking to him, he will give the player the Basement Key to access New Mauville City.
Head south of Mauville, towards the entrance to cycling road. Surf across, and head west. You'll eventually find a cave. That's New Mauville.
magnetons cannot be found in the wild, however you can find a magnemite in new mauville just outside of mauville
At new mauville after you beat your dad go to wattson and he'll give you directions
New Mauville city
you can get it after you beat the 5th gym. you go to mauville city and Watson is going to be there. talk to him and he will tell you to shut off t he generator in new mauville. you surf there ans you g=find a thunderstone at the end.
It’s in New Mauville, which is a cave on a tiny island southeast of Mauville City. You’ll need HM Surf to get there.
you get it in the NEW MAUVILLE basement
I would say the one on the way to de-activate the generator at new mauville near the cycling rode in Ruby, Sapphire, and Emerald.
just electric Pokemon eg.voltorb n maybe magneton or...
Mauville City But you have to beat the city's gym leader before you can turn off the generator in New Mauville City