- slide 1 of 11
Escaping the Trap
Wait for the platform to get close to the fire, then crouch and look above it. Fire one portal and wait for the platform to reach the end. Look to the right and fire a portal low on the wall, then jump through it to escape the fire. You’ll get a little burned but you’ll survive.
You need to pull off a simple slingshot to get to the manufacturing center. Put one up high by the fan and another in the middle of the floor. Drop through and then fling across to the equipment. Follow the path until you get to a locked door. Just use two close portals to get around it. You’ll come up to a few fans in a moment. Look through the fans and fire one portal through it. Put another in the wall and step through it to get around the fan.
- slide 2 of 11
Go down the ramp and look around. You should be able to shoot a portal across the gap right above the walkway. Put another one in the wall next to you and cross the gap. This catwalk doesn’t have anything to offer us. We need to get across. Go to the broken bridge and look. Shoot a portal above the fence and another close to you. Move forward a little bit so that you’ll fall over the fence and onto the catwalk. The office is actually a red herring. Walk down the catwalk toward the things that look like heating elements and go down the steps.
Put a portal through the fence and a little bit above the catwalk. Go through it to get a good vantage point. You can’t put a portal above the next segment of catwalk, so put one on the wall across from it and another on the floor. Slingshot over to the broken catwalk and move forward just a little bit more. You should come across one of the tubes that carries the tube around the complex. Drop into the tube through the hole and ride it through until the drop off point.
Drop down and back onto the test course.
- slide 3 of 11
Return to the Course
Run through the force field and step on the button. Fire a portal past the open door and another into the wall. Slip past the door and then drop down the elevator shaft. Fire a portal on the low ceiling and another onto the elevator shaft. Drop through to get past the locked door.
- slide 4 of 11
A Surprising Number of Pistons
Walk onto the second rising piston and ride it up. Put a portal onto the floor that you can get a glimpse of ahead of you. The only other place to go is the white wall you can in through on the low ceiling. Replace that one and climb up. You can crouch to squeeze between it and reach the portal, at which point you’ll go up to the top.
Wait for the next long pistol to go out and run across it until you get to the end. Fire through the gate to set up the portal and then run back ot the floor across the pistol to reach a white floor. Drop through to get to the other side and reach a cube carrying tube. Look up and fire one portal as high as you can. Put one on your level and use it to jump across to the other side.
There’s a big room of five tall pistons ahead. Get onto the center one (it’s high enough and won’t crush you on the ceiling. Use the height to shoot a portal through the tall exit and then go through a portal on the floor to reach the next path.
Follow it forward and watch for another set of pistons. Fire one above the next set of pistons and one on the impact point. Jump on the piston and let it carry you up through the portal. Hopefully it will drop you on the horizontal piston. If it doesn’t, drop back down and try again. Ride it back and jump across to the platform.
- slide 5 of 11
- slide 6 of 11
Look up and fire a portal above the long piston. Put another one on your level and drop down on the piston. Look over and put a portal on the middle section of the wall across from the catwalk. Drop off of the piston onto the catwalk, then drop down through a portal on the wall to slingshot to the side.
Walk forward to reach another set of fast pistons. Fire a portal past it to slip past them. Turn and face two large pistons. You can’t cross it in time, so fire a portal through and go through it. Look up to see a whole bunch of pistons.
Just try to aim as high as you can and drop off of the pistons. You ultimately need to drop onto the top pistons by firing a portal above them on the thin wall. Drop down on the pistons and quickly fire a portal onto the floor across from them. You’ll probably get pushed off quickly, so do it fast. Put another portal anywhere nad go through to get to the other side of the fence.
Walk through and drop down onto the tube system. Follow it down until you reach some toxic water. Crouch under the large piston and fire a portal onto the wall above it. Backtrack to the first room to get to some white wall and put one low. Jump through it when you can see the piston to land on it. Get across to the other side and jump down the hole.
- slide 7 of 11
Another Ambush and Escape
When you step onto the series of pistons, they’ll dump you down into a pit of turrets. Watch for the smoking door and get out of the way. There’s a turret behind each one. Get one portal somewhere and then quickly step out and fire a portal under the turret. Repeat this for each of the three turrets to take them out. There should be a hole in the ceiling for the third turret room. Fire a careful shot to form a portal and then go through it to get to the next area. Fire a portal higher to get onto the catwalk. You actually don’t have to kill the turret on the floor, since the escape point is marked on the side wall. Go through it to drop down on top of a turret destroy it and drop down.
It’s a pretty easy slingshot to get up to the catwalk in the middle. Walk out a bit and get a portal on the top of the raised diagonal platform. Put another portal close to it and go through for a standard slingshot. Walk along the walk until you get to the office.
- slide 8 of 11
Run through and get around to stand in front of the other glass and dodge the rocket to clear the next path. Move forward a bit more until you run into a third wall of glass. Put a portal across from it and walk back to the rocket turret. Put one on the wall and stand in front of it. Dodge the rocket and it should go right through and break the glass. Reset the portal and grab a chair on your way out of the office. Walk through to the broken glass with your chair and drop it off in front of the vent. Jump up into the vent and walk through to the fan. Shoot a portal through the fan and onto the white wall, then backtrack and go through it to get past the the fan.
Walk a bit further until you come up on another area. Stay out of the diagonal water and then fire a portal over the machines in the water. Go over to them and then fire another one diagonally. Go through it to reach the other side and look up through the drain. Fire a portal up above and go through it. Walk around the water and go up to the big area. Look out of the canals and fire a portal into the wall. Go up and drop down for one very big battle.
- slide 9 of 11
- slide 10 of 11
The Turret Battle - An Execution Room
Knock it over and look around. The little alcove should keep you safe. Just repeat this trick to get behind each of the turrets and take them out. Once the last one goes down, a new one will be revealed up top. Fire one behind it to take it out too. Now you need to put a portal onto the other raised diagonal panel and one on the ground. Go ahead and try to launch yourself up on top of the diagonal panel above us. You may not have enough momentum, so be ready to fire a new portal into the ground to fling yourself a bit further for a two-step slingshot.
Once you’re on top of the highest diagonal panel, put one portal here and one on the floor. Drop down into the portal fling yourself forward to the big area across from the highest point. Walk forward a little bit more.
Two more turrets will drop down. Get behind the pipes and put a portal somewhere. Lean out quickly and fire a portal under each of them to take them out. Once they’re down, put one portal on the floor under the big hole. Run back and drop down to the floor and use the momentum to slingshot up. Push yourself forward to get onto solid ground.
Aim high and put a portal above the catwalk. Drop down and walk through the door to find the long corridor. Walk along the path and through the office until you finally find GLaDOS herself.
- slide 11 of 11
Go ahead and fall for her obvious reverse psychology effort and grab the purple core that fell off. You need to carry it with you. Fire a portal above the incinerator. Walk over to the little booth and hit the button to open the incinerator (it takes too long to run to the incinerator, so you have to use a portal). Fire another portal and drop the purple core through it to drop it into the incinerator to start the big boss fight.
Run down. You have six minutes until the neurotoxin kills you, so move fast. The trick is pretty simple. We need to destroy the three main cores that make up GLaDOS.
It’s fairly simple. When you leave the little control room put a portal on a panel above so that it lines up with GLaDOS. Walk down and approach the rocket turret at any point and put a portal on the wall. Stand in front of it until the rocket turret locks on you and fires. Side step the rocket and wait for it to hit GLaDOS. Follow the green field to find the first part (it should just go off to the side). Dispose of it just like we got rid of the first one, by dropping it through a new portal into the incinerator.
Repeat the process another two times. I believe the second core lands on top of a floor above GLaDOS. Put a portal high above it and walk through one on the ground floor. You should fall onto it. Grab it and drop down to repeat the trick.
The last one just hung in the air for me. I repeated the portal trick and plucked it out of the air as I fell. Once the third core (the aggression core) is destroyed, GLaDOS will malfunction and you will be taken to the surface. Enjoy the finale.