Stopping Stirling from reactivating GLaDOS will require players to reach the Control Room to destroy the Spire for which players will have to complete test chamber 9, the final test chamber of Portal: Revolution.
In this guide, we’ll go over how to solve chapter 8 test chamber 9 in Portal: Revolution.
How to Solve Chapter 8 Chamber 9 in Portal: Revolution
Unlike the regular test chambers in which you have to open the exit door using the block or laser, the final test chamber will test your portal skills to climb up to the top to reach the Control Room. As players reach the entrance to Chamber 9, Stirling will trap them from where they have to open the portal to get out of the room. Upon following the steel staircase, players will reach the test chamber 9 area.
Look up to the railing beside the pipe, shoot a portal, and open another portal on the floor to go up. Now, shoot a portal on the wall beside the pipe and then jump down into the portal on the floor to cover the gap and reach the other side. Go inside the room and crouch down on the left side to see a broken vent. Shoot a portal through it and then open another portal to cross the vent.
There will be a giant fan in front of you through which you need to shoot a portal and then open another portal on the wall to cross the fan. Now, look up to see several floors above you and you need to start going up by aligning one portal next/close to the platform and another one on the floor. Jump through the portal on the floor to go up and you can even gain more momentum by going through the floor portal twice to cover gaps.
Once you have reached the top platform, go through the door on the left side to reach a room with a large pipe. Shoot a portal on the white wall above the door from where you entered and then go back to the platform and jump down on the floor to quickly open another portal to get across the gap. As you reach the other side, interact with the switch to close the door in the middle.
Now, open the portal on the door underneath the pipe opening and then go back to the platform to jump again. Doing it right will get you through the pipe and complete the test chamber 9. After that, players will reach the final area of the game where they will have to shut down the Spire by pressing the Red Button in each one of the Control Rooms.
Visit our guide of Chapter 8 Walkthrough to get more information.