Divine fire discharged by the containment breach traps, incinerating the surgical theater and burning the castle.
The eight Containment Breach Trap Mark IV modules mounted around the observation deck of the Surgical Theater are built to shoot literal Sheol fire into the room, incinerating everything instantly, and are triggered by anyone unaffiliated with The Madness setting foot on the floor. Carl judges his weakened Immortality probably enough to survive it, but knows Burcu would absolutely be turned to ash.
When the sequence fires, the flame descends on the room from all directions at once. Burcu dies. Carl escapes only through Gloom Wraith Phase, emerging unburned but injured, and the castle itself catches fire behind him.
Fire that descends into a room from every direction at once, hot enough to be felt through walls.
The lethal payload of Houston's trap ring and the fire that consumes the castle.
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