Metroid Prime 3: Corruption Part 26: The Fourth Part of Elysia
Work your way back to the Aurora Unit by taking the ball tube to your right. Go to the Rooms. You will need to use the kinetic Boost Balll in order to get across Skybridge Hera. Go to the opposite door of the junction, and make your way back to Spire dock.
After taking both elevators up, go outside onto a ledge and face off with three robots. Then find the ball tube and get in. You will soon find yourself in a familiar place, and will get a message saying that you need to get an Aurora Unit back on line. Follow your map to get to that Aurora Unit.
Once you get to that Aurora Unit, you need to find this device that you can enter in as a morph ball. From there, hit Boost and you’ll look like some sort of gerbil. This will create the power necessary to open the doors. From there, you will be asked to repair the unit, and it will open a maintenance hatch big enough for your Morph ball form.
You will then be in a room full of robots. They go down easily, and when they finally do, there is an access panel for you to upload the vaccine.
Then Ghor shows up and does some serious damage. Exit the room from the ball tube that you entered, and go and talk with the Aurora Unit.
From there, the Aurora Unit will tell you to hunt for Ghor. He is actually at your ship, trying to destroy it! You should go out of the Aurora room, up the elevator into the Save Room I mentioned earlier. Use your map to make way back to your ship, but there will be a few obstacles in your way.
For example, when you get back to the Steam Barracks, the one where you met the Steam Lord for the first time. You will need to jump into the kinetic generator and Boost Ball until it swings around. From there, a half-pipe like thing will appear, and you will need to Boost Ball your way up to the next level. This can be tricky, so what you need to do is hit the B button at the bottom of the pipe, and this will propel you very high.
There will be a lock there that requires you hit A at certain times to open. I really got stuck on this one. Just look at the circles, and twist the controls so the missing part fits in. After a few twists, it will open.