Player 1: Upon entering the test chamber hang a left and then set your first portal on a wall panel directly opposite the elevated platform and then your second portal on the floor panel underneath the propulsion gel dispenser. Press the button and the propulsion gel will coat the angled platform in preparation for the next steps. Player 2: Run up the orange runway and you’ll zip across the gap to the other side. Once you’re safely across, stand by the red button and start a 3, 2, 1 countdown.
Player 1: Just after the countdown is initiated, start running up the ramp and just before you reach the force field, player 2 should press the button to release the crate above. Press the catch button as you fly by to catch the crate and set it down on the square button at the other side. Both Players: Head through the force field, down the stairwells and onto part 2 of the test chamber.
Player 1: Drop down to the lower level and set a portal on the left-hand slanted wall pane (with the ‘2’ on it) and then place your next portal directly under the propulsion gel dispenser to the right. Press the button and watch as the gel coats the floor of where the metal spikes are falling. It’ll take a few tries to coat enough of the floor here as the spikes are constantly raising and falling (blocking your gel). Repeat the same steps with the slanted wall panel near you (labelled as ‘1’).
The next step is to leave the portal under the gel dispenser but place the other portal on the various wall panels on the upper ledge (including all the side panels and the roof panels). This should evenly coat the floor area of the ledges. Player 2: Get yourself up on the left-hand ledge and set a portal on the wall behind you and the one in front of you so you create an ‘infinite’ portal. Now start running and do not stop!
Player 1: Once player 2 has started to run in a loop, set a portal on slanted panel ‘2’ and then aim your portal gun at the right-hand wall and fire off your second portal just as they pass through their own portal on the right and this will allow them to shoot through and towards the spike plates. You’ll ideally want to listen out for the sound of them crashing down before you set your second portal off.
Once they’re safely past the spikes, get yourself onto the same platform your friend was on and set up your own infinite portal (one portal behind you and one in front of you). Start running and you’re now in the hands of your colleague.
Player 2: Place a portal on slanted wall panel ‘1’ and then time your shot into the right-hand wall so the spikes are just starting to rise back up again. If timed right, player 1 will soar through the air and past the spikes. Both Players: Stand on the red switches at the same time to release the crate from the chute in the middle of the room. Pick it up, drop it in the floor lock to open up the exit to the sixth chamber.