Brass Vent of the Ninth Clause
This infernal machine is a floor-bound sentry that exhales scalding brass needles and waves of hellish heat in a precise, repeating cycle. It is built to slow a group, force them into bad positions, and make the dungeon itself feel like it is breathing.
Brass Vent of the Ninth Clause
Defenses
Detection
“A brass and iron dais set into the floor, ringed with soot-black glyphs and six slowly turning spindles. Thin seams in the stone glow red when the hazard is awake.”
Standard Engagement
The hazard activates when a creature steps on the central brass plate, disturbs the control glyph, or otherwise enters the trapped corridor without speaking the command phrase.
On initiative count 10, if the hazard is active, it emits a low gonging note. Each creature of the DM's choice within 15 feet must choose one: move up to 10 feet away from the dais if possible, or make a DC 14 Dexterity saving throw. On a failed save, the creature takes 1d8 fire damage and cannot take reactions until the start of its next turn. Creatures that remain within 10 feet after the routine also suffer the Heat Haze effect. If two or more creatures are within 10 feet, the hazard instead targets the two closest creatures with brass needle jets, each making a separate DC 14 Dexterity saving throw against the same damage.
The hazard resets after 1 minute of inactivity if at least one spindle remains unjammed. If fully disabled, it remains inert until repaired by a creature with tools and the proper command phrase or infernal sigils.
The nearest creature within 10 feet of the dais must make a DC 14 Dexterity saving throw, taking 2d6 fire damage on a failed save, or half as much damage on a success.
Any creature that starts its turn within 10 feet of the dais must succeed on a DC 13 Constitution saving throw or have its speed reduced by 10 feet until the start of its next turn, as the heat buckles the air and steals breath.
While active, the hazard rewards movement and punishes clustering. If a creature is pushed, dragged, or forced into the hazard's 10-foot zone, it immediately makes the same save required by the routine.
If a creature rolls a natural 1 on a disable attempt, the hazard immediately gains one extra success on its next routine, representing an overpressure build-up in the vents.
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