Icicles hang tenuously from the ceiling. A failed Dexterity save knocks 1d20 icicles loose. They fall to the ground and shatter, creating a frosty mist that refreezes in the nasal passages and lungs, causing 1d6 damage for 1d4 rounds until melted.
The ice particles melt in 3 minutes.
A successful Fortitude or Constitution saving throw prevents fainting from suffocation. If a creature faints in the room, more icicles fall to the ground and the process repeats.