Learn about your next mission, and you can talk to everyone here if you like, but to continue you need to talk to Tifa. When the ID Check discovers you, you have 15 seconds to get to the next car in line each time. You can talk to the people in the cars but it’s just a waste of time. When you are running through the third car, someone walking past will nick some of your Gil. You can get it back, by talking to him twice and picking the second option before exiting to the next car. Rub through the cars until you get to the end of the train. Talk to Tifa and you, Tifa and Barret will jump off the train, into the sewers below.
From where you jumped off, you can either go north or south. If you go south, after a few screens some guards will turn up who you can fight. After you beat them, more will come out. Each time you have an option to fight or run, so you can fight this battle as many times as you like. It’s good for EXP, Gil and AP. Once you are done there, or just want to continue without fighting the guards, go north. You will arrive at a green beam security barrier. There is a shaft to the left. Examine it with O, and choose to top option twice.
Go to the right and pick up the Ether. Go down the ladder. In the next screen, go down, left and down the ladder again. Go down the stairs and to the left, ignore the ladder in the middle. Talk to Wedge and go up the ladder to meet Jessie. Take the Potion to the left, and go down the ladder to the far left, not the one next to Jessie. Keep going down the ladder and go the right to pick up a Tent and find the Save Point. Talk to Biggs and go up the ladder to enter the plant.
Go down the chute to the right, and go to the left and through the door. This should look familiar, as it is the same layout as the previous Mako Plant. Jump the gap, go down the ladders, allow the pipes, down the next ladder, (you can save if you want) and across the walkway to get to the area where you set the bomb last time. Watch as Cloud goes freaky again, sets the bomb and then make your way back to long flight of double stairs. Go up them, ride the elevator, get the Ether from the chest and go into the room to the left with the three panels. Working the panels can take a while if you don’t get your timing right. Wait a few seconds after Tifa stops talking then press O to raise Cloud’s arms just before Tifa and Barret do. This should make the door to the right open go through it to a Save Point and prepare for the next boss. Go down the stairs to the left then run up the walkway to the T-Junction where Shinra soldiers will appear, blocking you in. Don’t worry, you won’t have to fight them. President Shinra will appear, talk to you for a while then escape on a helicopter, leaving you will a weird, floating machine type thing to deal with…
Air Buster
This boss will separate Cloud from Tifa and Barret, allowing you to attack it from both sides. But this boss will turn to face and attack whoever attacks it. This boss is easy if you have been levelling up with the guard battles in the sewers. After you damage it enough it will be unable to turn to attack so will just attack whoever is behind with a weak machine gun. It also has a shockwave attack that can be quite nasty but fills up Limit gauges. Also whoever has Restore materia can only use it on whoever in on their side of the boss, not on the separated ally(ies). Use Bolt magic and Limit Breaks. You will win a Titan Bangle after beating it.
The boss will explode and blow a hole in the walkway, and the bomb explosion will send Cloud falling into the slums below.