Blinding Crawler

Incorporeal Movement. The wraith can move through other creatures and objects as if they were difficult terrain. It deals 5 (1d10) force damage if it ends its turn inside an object.

Darkness Sensitivity. While in darkness, the wraith has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Blinding Aura. The Crawlers emit a sickly blinding light. Creatures within 5 feet of the Crawler must make a DC 14 Perception check at the start of each of their turns or have disadvantage on their attacks while within the 5 feet.

Quicksilver Sensitivity. Attacks with a melee weapon that has been coated with quicksilver deal vulnerability damage (double damage)

Life Drain. Melee Weapon Attack: +8 to hit, reach 5 ft., one creature. Hit: 21 (4d8 + 3) necrotic damage. The target must succeed on a DC 14 Constitution saving throw or its hit point maximum is reduced by an amount equal to the damage taken. This reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hit point maximum to 0.

Necrotic burst. AOE Spell Attack: Hit: 21 (2d10 + 3) Enemies within 10 feet of the Crawler must succeed on a DC 15 Con save or be hit with 2d10+3 necrotic damage. This ability regains charges on a 5 or 6.

Create Specter. The Crawler targets a humanoid within 10 feet of it that has been dead for no longer than 1 minute and died violently. The target's spirit rises as a specter in the space of its corpse or in the nearest unoccupied space. The specter is under the wraith's control. The wraith can have no more than seven specters under its control at one time.