Final Fantasy VII Walkthrough – North Corel Reactor
Items: Ultima Materia (for stopping the train)
To Enter the North Corel reactor go through the Gold Saucer entrance area and head north. Save before you go through though. Go over the rope Bridge and follow the track back to the reactor. As you enter you'll see a train coming from the entrance to the reactor, you'll jump on the train and make your ways down the carriages, you'll have to fight on every one. You'll be given ten minuets to make your way to the front; you have to be strong for these fights. Also avoid using summons as they take up time, just use your comet1/2 magic and powerful attacks, Trine enemy skill is also useful on these mechanical enemies.
Fight 1: Gas Ducter: Weak against Lightening so use Bolt's and normal attacks
Fight 2: Two Gas Ducters
Fight 3: Wolfmeister. Weak against water, in normal circumstances I'd say kick its butt with Leviathan but that takes too long
Fight 4: Eagle Gun: Weak against Lightening, Trine Enemy skill is useful along with Bolt2/3
Fight 5: Attack Squad: Kill quickly with regular attacks
Jump onto the driver's carriage and Cid will have to stop the train, to do this Alternate both levers until the brakes work. You see an FMV or the train stopping just before North Corel. You'll get Ultima from the people of North Corel for this, which is a very powerful Magic Materia. You'll also have the huge materia.
If you couldn't stop the train you'll have to pay 50,000Gil for Ultima. You can now get Barret's ultimate limit break if you stopped the train as well. Your next destination is Fort Condor so don't buy Ultima yet because you'll need to save your Gil.