Cultist Witch

Dark Devotion. The cultist has advantage on saving throws against being charmed or frightened.

Eldritch Force. The first time in a turn the cultist hits a creature with their Eldritch Blast, the cultist pushes the creature 10 ft. away from them or pulls the creature 10 ft. towards them.

Spellcasting. The cultist is a 12th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 16, +8 to hit with spell attacks). They regain their expended spell slots when they finish a short or long rest. The cultist has following spells prepared:
Cantrips (at will): Eldritch Blast, Mage Hand, Thaumaturgy
1st-5th level (2 5th-level slots): Arms of Hadar, Cause Fear, Command, Ray of Enfeeblement, Dispel Magic, Hypnotic Pattern, Black Tentacles, Blight, Cloudkill.
6th level (1 6th-level slot): Mass Suggestion.

Multiattack. The cultist fires three eldritch blasts.

Dagger. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 3 (1d4 + 3) piercing damage. 

Eldritch Blast. Ranged Spell Weapon Attack: +8 to hit, range 60 ft., one target. Hit: 10 (1d10 + 5) force damage.