Soon after picking up the portal gun, you'll be told:
"Do not touch the operational end of The Device."
"Do not look directly at the operational end of The Device."
"Do not device submerge The Device in liquid, even partially."
"Most importantly, under no circumstances should you [bzzzpt!]"
In the English version of the game, the last line is interrupted by static. When the audio is switched to Russian, however, this line is not interrupted, and the script roughly translates to:
"Most importantly, under no circumstances should you remove the device from the testing area."
Why not?
A voice line that isn't implemented (but still found in the files nonthless) makes it clear enough.
"Stop! The device will detonate if removed from unapproved testing area."
Guide help
This is the low-spoiler guide for "Under no circumstances should you..." 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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