Metroid Prime 3: Corruption Part 39: The Fifth Part of Pirate's Homeworld
Head back to your ship. Go to the Pirate Homeworld, and you’ll get a transmission from Admiral Dane saying that they are ready to invade the Homeworld, but need you to bring down the defense system. They will give you a set of coordinates.
Go to Landing Site Alpha, and then enter in to Transit Station 1-B. Take the train to the next location. Work your way back to Proving Ground, the one area where you defeated Gandrayda, and take the elevator down. You will soon come to a room known as AirShaft, where there is a magnet rail. Z attach yourself to it via Spider Ball and go. Soon you will come to a small room, and there is another ball tube to enter.
You will then come to a place where there is a rotating tower. You will see an entrance point that will lead you to a dead end. To the right of the entrance points are two ball holograms, like the types that are in the cannons at Skytown. What you need to do is get into them and hit “B”. The left one does turns the bottom level, while the other turns the top. What you need to do is get them so that they will line up and give you a perfect Magnet path to the top. Concussion bomb out of there, and magnetize yourself.
Keep rolling until you reach a control room. Activate the handpad, and you will receive something very special. You will now be resistant to acid rain and fuel gel.
A few flying bad guys will then show up and try and beat you. They are immune to missiles, but vulnerable to other weaponry. After they are defeated, you will see a hand pad near the routing tower. Use it, and some doors will open. Defeat the bad guys with some Phazon or the old-fashioned way, and then jump up some nearby ramps to the hallway you were in before you magnet-rolled. Head directly to the place where you one door has a shield vulnerable to extreme cold. Blast it, and enter in.
You will find a ball tube opening that you can blast off. Enter in, and you should be roll until you get to a place where you must turn the path to go any further. Go to the dead center of this circular thing and hit Boost Ball. Go and get the missile upgrade, then roll out of there the same way you came in.
You are now invulnerable to acid rain, so cross over to the other side until you see a green ledge. Jump on and go up. There is some Phazon crystal blocking the way, so take it out with a Hypermissile. Go ahead and enter into the next room.