Cultist Leader Lord Callian

Magic Resistance. The archmage has advantage on saving throws against spells and other magical effects.

Spellcasting. The lord is an 9th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 17, +9 to hit with spell attacks). The lord can cast disguise self and invisibility at will and has the following cleric and wizard spells prepared:

Cantrips (at will): fire bolt, word of radiance, mage hand, prestidigitation, shocking grasp

1st level (4 slots): command, identify, mage armor, magic missile

2nd level (3 slots): hold person, mirror image, misty step

3rd level (3 slots): counterspell, fly, lightning bolt

4th level (3 slots): banishment, fire shield, stoneskin*

5th level (1 slots): cone of cold, scrying, wall of force

Multiattack. The lord can use Nessians Glare and makes one attack with the fist of Callian.

Fist of Nessian. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 10 (2d6 + 4) bludgeoning damage plus 10 (2d6) necrotic damage. If the target is a creature, it must succeed on a DC 12 Constitution saving throw or be cursed with Nessian's rot. The cursed target can't regain hit points (1d4) for every 24 hours that elapse. The curse lasts until removed by the remove curse spell or other magic.

Nessians Glare. The lord targets one creature it can see within 60 feet of it. If the target can see the lord, it must succeed on a DC 13 Wisdom saving throw against this magic or become frightened until the end of the lord's next turn. If the target fails the saving throw by 5 or more, it is also paralyzed for the same duration. A target that succeeds on the saving throw is immune to the Cultist Glare of all cultists of Nessian for the next 24 hours.

The lord can take 2 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature's turn. The lord regains spent legendary actions at the start of its turn.

Attack. The mummy lord makes one attack with Nessians fist or uses Nessians Glare.

Blinding Dust. Blinding dust swirls magically around the lord. Each creature within 5 feet of the mummy lord must succeed on a DC 15 Constitution saving throw or be blinded until the end of the creature's next turn.