I’ve been busy with it now for less than a day, not even done yet, but I’ve only run into one room where I scratched my head for a longer time. Not going to give anything away here, just describing to you how that room looks like and how to solve it, so you don’t have to get a sleepless night over it. So if you are not looking for a solution, then avoid the rest of this post.
The room is fairly late in the game, where you found the potato and there are gels in the modern environments. It’s room 17 or 18 in that portion of the game.
As you enter you see a gap in front of you, a blue tunnel going from right to left above you and completely over the chasm, a ledge at the far end of that chasm with a blue gel dispenser in the ceiling and a button on the lower left. Now turning your attention to the right of the door, is a button, turning the tunnel orange, reversing it’s direction and a shielded wall with three turrets behind it. There is a button there to press as well, guarded by the three turrets. The exit is to the very far right, behind the turrets over another huge chasm.
In short, the turrets have to go and in the process they create what you need to escape. Portal to the gel dispenser, setup that the tunnel goes straight back towards the door where you came in and hit the button. Gel comes out and fills the tunnel. Make it drop once on the ledge of the chasm, so you can hop into the tunnel from there. Then establish the tunnel again, hit the button, and don’t wait for it, but jump into it as soon as possible. Let it carry you across, then hop on the button reversing the flow. Now wait for the gel to make it all the way back into the portal and nearly to the emitter of the tunnel, but past the portal. Now shoot the portal that’s not on the top left portion on to the wall you can see to your right and up, above the turrets. With the tunnel going out, step away from the button. The gel should now be transported back through the portal and start to move over the turrets. Stop the tunnel, let the gel hit the turrets and see them bounce off. This also paints that area nicely.
Now go around the shield, press the button. A panel opens behind you and goes at an angle. beside it, to the right, open a portal so the tunnel appears and pushes you upwards. Ride it to the top. Now shoot the portal that’s facing the tunnel generator on the slanted surface. You drop into the portal below you, get flung out of the diagonal surface, bounce on the gel and then straight into the exit.
Enjoy Portal 2 and hopefully you won’t get stuck anywhere like I did.
