Extreme Cold

D&D 2024 hazard: Extreme Cold. Source: Dungeon Master's Guide (2024). hazard type Environmental Hazard When the temperature is 0 degrees Fahrenheit or lower, a creature exposed to the extreme cold must succeed on a 10 Constitution saving throw at the end of each hour or gain 1 Exhaustion level. Creatures that have Resistance or Immunity to Cold damage automatically succeed on the save.