"Standing directly in front of a door and hitting it with a hand."
So no device set up beforehand is allowed. Also,
Let it be known that in addition to Krauss, Natsuhi, and Genji, none of those in the dining hall made the knock. In this sense, 'knock' includes all direct, indirect, intentional, unintentional, and coincidental events that could create a knocking sound.
From: CalvinbalI | #038
And the second statement is so...fuzzy. Like if someone sets up a device prior to the family conference that is on a timer, does that count as them influencing something inside the mansion around the time of the family conference? They influence the environment inside the mansion prior to the family conference, but then it's only the device influencing the mansion during the family conference.
It's not fuzzy. It means that nothing they have done, ever, can cause any influence inside the mansion at that time. Influence means 'the action of producing an effect', so even if it was set up beforehand, they'd still be 'producing an effect in the mansion at that time'.
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