Activation

"Kamchatka Peninsula is mostly permafrost and volcanic rock," Hermione said. "There are natural caves and fissures, but the Technical Group's scan report didn't mention any underground passage leading to the main chamber at the eighth site. If one existed, it should have been there when the system was built."

"What if the builders left a backup passage?" Ron suggested. "Like that buried door beneath Hogwarts."

Harry slipped his phone into his pocket and paced the room a few times.

"If I were the builder, I'd leave at least one backup passage besides the main entrance, for emergencies or repairs. It might not be marked on any map, or it might have been sealed off, but I'd keep it there just in case. The Confederation's remote scans only covered the standard depth range. If the entrance is deeper, or hidden beneath some kind of shielding material, the scans might have missed it."

Hermione set the report on the table.

"If the client found that passage, they could bypass the Monitoring Runes and go straight into the chamber containing the pillar."

Harry took out his phone again and sent Rosier a message: "Can the Technical Group run a deep geomagnetic scan around the eighth site? Extend it to fifty meters and look for any unrecorded passages."

Rosier replied that evening: "The Technical Group is arranging it now. Data collection and analysis should take four days."

Over those four days, Harry went to class as usual, ate in the Great Hall, and spent his evenings with Hermione in the Common Room, reading the Technical Group's progress updates.

On the third evening, the Technical Group sent its preliminary analysis of the first deep-scan data. It had found an anomalous signal band roughly forty meters east of the depression.

It lay about twenty meters underground,