You're back in test chamber 09! Last time you were here, you could only create blue portals. Doesn't time fly?
What do I do?
The first time you were here, you used a cube to activate the button. There's no cubes here now, though.
Help me out.
Stand on the button, and create a portal on the other side of the door while it's open.
You should then make another portal somewhere in the room to proceed.
Guide help
This is the low-spoiler guide for "Emerging from the tube" puzzle in Portal. Unlike in normal walkthrough, you get gradual hints on how to solve the puzzle. Click the big button below to see your first hint. If the hint contains a spoiler, you will be warned about it before clicking.
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