Continue straight along the railed path through the circular door.
Continue on the railed walkwaythrough another door that opens into an energy field.
Go through andshoot one portal on the high wallto the right andone on the ground directly underneathit.
Go through and thenfall through the portal on the ground.
If your higher portal is in the right place,this should launch youacross the gap.
You may need tomove your higher portal if it is getting blocked by the metal frameworkwhen you launch yourself.
Once across, continue walking until you get to a pipe that is moving gel.
Once there,shoot a portal near the edgeclosest to where you came from andone on the ground below.
If successful,you’ll move enough to land on the next section.
After that,shoot a portal on the opposite edgeof where you came from.
Then, turn around,shoot a portal through the rectangular hole into the ground, then jump through.
Wait for the claw to fully dropand open before placing Blue inside, otherwise you may face a glitch.
Once your hands are free,press the big red button to begin the final battle.
The door on the right will open after Stirling activates the five-minute timer.
Go through the door and energy field beforedropping through the windowto the lower level.
Go through the door that opens into the Spire’s Core.
Shoot one portal on the wall close to youandone across the way to the platformnear the button.
Take the cube through the portal andplace it on the button.
Drop down andgo through the now-opened doorbeforestepping on the launcher.
Go into the control room after you make it across andshoot one portal on the ground.
Next, peek around the corner toshoot a portal behind the turret on the right.
Grab it and throw it todeactivate.
Now you canrun along the left-side of the room’s walland knock over the last turret.
Once you’re alone,shoot a portal on the wallwhere you came in andone on the ground.
Take the cube through and put it on the button.
Go through the door and energy field into the next room.
Go through andknock it over.
Next,shoot one portal on the groundandone high on the wall.
Go back into the room andshoot the other color on the wallbefore reaching through and grabbing the turret.
you could eitherknock it overor throw it into the energy field where you came from.
Step inside tolift yourself high into the air.
Once you’re high up,shoot the portal under the tractor beam dispenser on the slanted wall.
This should allow you tofall through the portal and be launched across the roominto the final section.
Go through the door and energy field.
Peek through the window andshoot a portal behind the turretandthe other color behind you.
Go through andknock over the turret.
Next, go back through the portal and peek behind the pipe toknock over the turret.
Then,shoot one portal above the grated areaandone on the ground.
Continue watching after the creditsto get a scene giving context to what happens after the final button push.
