So, I was just playing some Pok�mon Emerald and I came across Magnemite on the out skirts of Mauville from a quest Gym Leader Wattson gave me. So I caught it, once it reach level 30 it evolved into Magneton! I know you can evolve it one more time. So I went back to Mauville and at this point I already have Fly and my 6th gym badge. So I try to find a place inside Mauville to level it up, there is no where to fight. Since I already beat the Gym there I can't battle anyone or anything in Mauville so I can't level up Magneton inside Mauville so it can't evolve into Magnezone. I leveled it up right beside Mauville in route 110, 110, 117, and in 118 , not so surprisingly nothing happened.
Question is, how can you level Magneton up in Mauville
after you've already beaten Gym Leader Watson and the people inside it. There is probably a simple answer out there that I couldn't find anywhere else on the Internet.
Thanks