Apito's seal traps guests in their ballroom, forbids violence, and banishes anyone responsible for breaking peace into the Nothing.
Entering Ballroom A mutes spellcasting, peace-bonds inventory, and prevents invited guests from leaving until the party concludes or the seal breaks. Once Imogen arrives, party chambers become fully closed to outside influence.
Violence does more than trigger guards. The floor opens and feeds those involved in the breach into the Nothing, an eternal realm of darkness and gnashing teeth. Imogen cannot harm guests before the ritual and even stops herself from attacking Britney when she realizes the crawler has entered the top fifty.
The threat forces Carl to change from initiating the operation to partying, preparing defenses, and waiting for someone else to break the peace.
A sacred oak-pattern seal across ballroom doors and floor, with a black void visible beneath cracks.
The seal invalidates the planned first strike and defines the only conditions under which combat can begin.