The Samsara Thearch was surprised by the weapon's form, but he was sure since it was transformed under the influence of the Unbreakable Spirit Sacred Mountain, it would be perfect for Codicia.
After the castle absorbed all the energy from the Unbreakable Spirit Sacred Mountain, Zatiel activated the cold energy of the Daybreak Universe's moon and gave it stability and endurance.
Zatiel took it out of his lungs, and when he focused on the small phantom castle, his mind lost itself in its illusion power for a fraction of a second. His willpower had to come into effect in order to wake him up.
Of course, had the Samsara Thearch activated his soul defenses, the castle would not have managed to pull his consciousness, but the weapon's power would increase immensely in the hands of the Unbreakable Spirit Sacred King.