Black Dragon

Regional Effects

Source: Monster Manual (2024)

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

• Acrid Haze. Odorous and stifling fog covers the area within 1 mile of the lair, rendering that area Lightly Obscured. Travel for creatures other than the dragon and its allies takes twice the usual time in that area.
• Foul Water. Water sources within 1 mile of the lair are supernaturally fouled. A creature that drinks such water must succeed on a DC 15 Constitution saving throw or have the Poisoned condition for 1 hour.

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