As several others have said (but perhaps not quite clearly enough...)
The " ~ " key is a toggle.
Press it once, the Command Console opens.
Press it again, it closes.
(Fairly simple, but I agree that it would have been nice to have had some instructions!)
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I had the exact same frustration with the "Run" key early in my first playthrough. I hit whichever key it was mapped to at the time by accident, then couldn't figure out how to STOP running! 😃
My Quizzy went over more than one cliff, and I swiped my palm across the keyboard several times attempting to get lucky before I finally understood what was going on!
