Prison of Fire

A permanent wall of fire lines every inch of this stronghold space’s outer walls, ceiling, and floor. A prison of fire takes normal damage from cold (not one-quarter as most objects). If any 5-foot length of the prison of fire takes 20 or more points of cold damage in a single round, the flames go out in that section for 1d4 minutes.

Caster Level: 7th; Prerequisites: Craft Wondrous Item, wall of fire; Market Price: 14,000 gp.