Death Gazer

Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 1 piercing damage.  The target must make on a DC 13 Constitution saving throw, taking (2d10) necrotic damage on a failed save, or half as much damage on a successful one.  On a failed save, a creature has its hit point maximum reduced by the amount of damage it took for 1 hour.  A lesser restoration or remove curse spell ends the effect early.  

Eye Rays. The spectator shoots up to two of the following magical eye rays at one or two creatures it can see within 90 feet of it. It can use each ray only once on a turn.

1. Negative Energy Ray. The target must succeed on a DC 13 Constitution saving throw, taking (1d12) necrotic damage on a failed save, or half as much damage on a successful one.  If the gazer targets an undead, the creature gains (1d12) temporary hit points.  The gazer can instead target a corpse of pile of bones with the ray, causing it to rise up as a zombie or skeleton.  If the gazer targets a severed hand, it creates a crawling claw, and if it targets a pile of flesh, it creates a boneless.  
2. Paralyzing Ray. The target must succeed on a DC 13 Constitution saving throw or be paralyzed for 1 minute. The target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success.
3. Draining Ray. The target must succeed on a DC 13 Wisdom saving throw or suffer one level of exhaustion.  While the exhaustion remains, the creature can't take reactions.  The exhaustion ends after 2 hours, or if the party takes a short or long rest.  If the saving throw fails by 5 or more, the target falls prone  
4. Enervation Ray. The target must make a DC 13 Constitution saving throw, taking 13 (3d10) necrotic damage on a failed save, or half as much damage on a successful one.  A creature who takes this damage can't regain hit points until the start of the gazer's next turn.    
5. Sickening Ray:  The target must make a DC 13 Constitution saving throw, taking 9 (2d8) poison damage on a failed save, or half as much damage on a successful one.  On a failed save, a creature is poisoned for 1 hour.  While poisoned in this way, the damage for a creature's weapon attacks is halved.  At the end of its turns, the creature can repeat this saving throw, ending the effect on a success, and taking 3 (1d6) poison damage on a fail.  
6. Reaping Ray:  The target must succeed on a DC 13 Constitution saving throw, taking 10 (3d6) necrotic damage on a failed save, or half as much damage on a successful one.  The gazer regains an amount of hit points equal to half the amount of damage dealt. 

Death Gaze (Recharge 6).  One creature that the gazer can see within 60 ft. of it must make a DC 13 Constitution saving throw, taking (5d8) necrotic damage on a failed save, or half as much damage on a successful one.  On a failed save, a creature is also blinded until the end of its next turn and is incapacitated while blinded in this way.  If the saving throw fails by 5 or more, the target is reduced to 0 hit points.

Undead Spawn.  The gazer stares at a creature that has 0 hit points and is still alive.  That creature immediately dies, and rises up as a ghoul at the start of the gazer's next turn.  In 2d10 minutes after the gazer uses this bonus action, a will o' wisp forms in the space of the dead humanoid.  The ghoul is under the gazer's command for 24 hours, while the will o' wisp acts on its own.