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From Pathfinder Gamemastery Guide, which isn't enabled.

Brown Mold

HAZARD 2
Stealth +11 (trained)
Description This unassuming fungus leeches heat out of the air.

Disable DC 18 Survival (trained) to safely remove the mold

AC 18; Fort +11, Ref +5
HP 30 (BT 15); Immunities critical hits, fire, precision; Weaknesses cold 10

Emit Cold (aura, cold)

5 feet. Brown mold deals 2d6 cold damage to nearby creatures.

Leech Warmth
Trigger Fire comes within 5 feet of the brown mold.

Effect The brown mold expands into every square adjacent to its space. As it grows, it pulls more heat from its surroundings, dealing 2d6+6 cold damage (DC 18 basic Fortitude save) to creatures within 10 feet after it expands.
Reset After expanding, the brown mold can't grow again for 1 day.
Pathfinder Gamemastery GuideOGL