Portal 2 After Elevator Shaft
Examine all the vitrified test chamber doorsIn, there are six sealed metal doors marked VITRIFIED ('Vitrified Doors') that have buttons in front of them that play unique audio clips of Cave speaking. At the beginning of Chapter 6 you'll have to penetrate the 1960s Aperture facility. After flying through the Aperture logo you'll come to an area with a tall elevator. You must use the elevator shaft as a gravity boost to get across a chasm. On one end of this chasm is a platform with three of the Vitrified Doors.
Portal 2 Walkthrough Text Only Version. Take the elevator up, place your portal on the ramp in the distance, and then fling yourself by jumping down the elevator shaft. Welcome to the Alpha tests! Turn on the switch and make your way forward into some proper puzzles. This Portal 2 walkthrough will cover Chapter 7, The Reunion. It's time to meet back up with our favorite potato, GLaDOS. If you need some help with the red gel tests, or you just can't figure out how to hit the button hanging in the air at the start of Chapter 7, just look here at this guide to Portal 2, Chapter 7. The Elevator Shaft.
Listen to the audio that plays when you hit the buttons in front of each of the sealed doors.Now, play through the level until you get to the 1971-era test facility. At this point, Cave will start talking about testing on hobos and you'll know you are in the right area.
Portal 2 After Elevator Shafts
Below one of the test spheres and a giant Aperture logo in its 70s cooper Black Font is a room marked CONTROL ROOM in yellow lettering. You can use a portal to get high above the Control Room and enter a small office. In the corner of this office is a cabinet with a door behind it.
Enter this door to find a secret hallway that leads to a dock (see Ship Overboard Achievement /Trophy). The final three Vitrified Doors can be found here.