Demilich

Regional Effects

Source: Monster Manual (2024)

The region containing a demilich’s lair is twisted by its presence, creating the following effects:

• Enervating Domain. Whenever a creature other than the demilich or one of its allies finishes a Long Rest within 1 mile of the lair, the creature must succeed on a DC 20 Constitution saving throw or have its Hit Point maximum reduced by 1d4. This reduction lasts until the creature finishes a Long Rest outside that area.
• Travel Ward. Creatures can’t use teleportation or planar travel to enter or exit the lair.

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