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Chapter 8 - Part 9: Chamber 12
sp_a4_laser_platform.bspLaser Platform
This is the fifty-fourth level of the game, and takes place within an incomplete Aperture Science Test Chamber and the maintenance areas of the facility. This level introduces the Laser Field, and features the Thermal Discouragement Beam as its primary mechanic.
Fire a portal at the end of the Thermal Discouragement Beam and the other one on the wall on the left activating the lower recepticle.
Wait for the platform to move to the left and then shoot a portal on the wall above it.
Go through the portal and land on the platform.
Shoot the same portal at the end of the Beam activating the platform.
When the platform is halfway through, shoot the other portal on the wall above disabling the laser field.
Move to the other side of the wall and fire the same portal on the wall activating the moving platform.
Wait for the platform to move to the other side and then drop down to the floor.
Wait for the platform to move to the other side and then fire a portal on the wall next to you.
Push the Switch and fire a portal on the wall above the plaform. Go through the portal.
Place a portal at the end of the Beam and then put the other portal on the wall opposite of the lower receptacle.
Wait for the platform to be halfway through and then fire the same portal on wall opposite of the upper receptacle.
Pick up the Discouragement Redirection Cube and go to the other side of the laser field and then place the same portal on the wall activating the lower receptacle again.
Wait for the platform to be completely on the other side an then fire the same portal to the wall directly on the opposite wall.
Aim the cube to activate the receptacle on the opposite wall. Then go to the left and drop down to the area below.
Shoot one of the portals on the wall near you and go through it.
Place the portal back where it was and go in the Chamberlock.
Go in the Excursion Funnel and wait until Wheatley turns it off.
Go through the door in the corner and drop down from the catwalk to the lower one.
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