White Dragon

Regional Effects

Source: Monster Manual (2024)

The region containing an adult or ancient white dragon’s lair is affected by its presence, creating the following effects:

• Frigid Cold. The area within 1 mile of the lair is an area of extreme cold. Any water in that area is frigid water. See the “Dungeon Master’s Guide” for rules on extreme cold and frigid water.
• Glacial Gloom. The area within 1 mile of the lair is Lightly Obscured by chilly fog. Whenever a creature other than the dragon or one of its allies finishes a Long Rest in that area, that creature must succeed on a DC 15 Constitution saving throw or have its Speed reduced by 10 feet for 1 hour.

If the dragon dies or moves its lair elsewhere, these effects end immediately.