Firstly, head south of mauville city and the cycling road entrance should be on your right, and an old man on your left. Head down until you're on the edge of the water (You need to obtain surf and beat the fifth gym leader.) then surf down until your next to a green tree. Then surf right until you see a cave entrance, go in and unlock the metal door. (You need to have talked to the 3rd gym leader when he was outside his gym.) when you go in you need to turn of the huge generator that has been running for 50 years. Available Pokemon are: Magnemite (Common) Voltorb (Common) Magneton (Very rare) and Electrode (Very rare). Some of the pokeballs on top of switches are, in fact, Voltorbs. When you turn the generator off, go back to the 3rd gym leader and he will give you the TM24 (Thunder wave). I recommend that you bring repels so you make this job alot faster. Also, to make the job at least x2 faster, bring an escape rope, to escape right after you turn off the generator.
By Josh the greatest!
Next to the pokemon center in Mauville
step on a button in front of the generator
the daycare in Pokemon ruby is between verdanturf city and mauville city
The Day Care in Pokemon Ruby is on the route West of Mauville City.
After a certain point in the game, you will see Watson standing in the middle of Mauville outside of his gym. If you talk to him and agree to help him with his problem, he will give you the key to New Mauville.
new mauville after you get a key from Wallace
New Mauville city
New Mauville is located on Route 110, underneath Cycling Road.
Next to the pokemon center in Mauville
Under the cycling road, to the right. You have to know surf.
step on a button in front of the generator
on mauville city
Mauville
the daycare in Pokemon ruby is between verdanturf city and mauville city
The Day Care in Pokemon Ruby is on the route West of Mauville City.
After a certain point in the game, you will see Watson standing in the middle of Mauville outside of his gym. If you talk to him and agree to help him with his problem, he will give you the key to New Mauville.
To get flamethrower on Pokemon ruby you have to learn it or you just have to buy it at the game corner in mauville city.