Brown mold feeds on warmth, drawing heat from
anything around it. A patch of brown mold typically
covers a 10-foot square, and the temperature within 30
feet of it is always frigid.
When a creature moves to withi n 5 feet of the mold
for the first time on a turn or starts its turn there, it
must make a DC 12 Constitution saving throw, taking
22 (4d10) cold damage on a failed save, or half as much
damage on a successful one.
Brown mold is immune to fire, and any source of fire
brought within 5 feet of a patch causes it to instantly
expand outward in the direction of the fire, covering a
10-foot-square area (with the source of the fire at the
center of that area). A patch of brown mold exposed to
an effect that deals cold damage is instantly destroyed.
