Amon was taken out of his prison cell ten days after he was captured. From what he could perceive, they were underground, as were most of the rebels' hideouts. The setting was similar to the hideout where he was captured the first time when he was still a student at the Royal Academy. He was brought into a large hall filled with people.
He was carried onto a stage at the center of the hall. A large metal crucifix was at the stage's center. He was tied to the crucifix using engraved chains.
The engraved chains were stronger than the engraved ropes. Engraved ropes were only strong enough to bind a cultivator until the Mystic Stage. To bind a Spirit Stage or even a Lord Stage cultivator, one required the engraved chains. For the rebels to use these engraved chains to bind him, he took it as a sign of honor.