Aribel Von

Innate Spellcasting (Psionics) Aribel Von is a 13th-level spellcaster. Its spellcasting ability is charisma (spell save DC 18, +9 to hit with spell attacks). Aribel Von has the following warlock spells prepared:

Cantrips (at will):  Green-Flame Blade, Eldritch blast, Sword Burst
1st level (10): Ray of Enfeeblement, Misty Step, Shadow Blade

2nd level (8): shatter,

3rd level (6): thunder step,  counterspell,

4th level (5): Blight, enervation

Multiattack Aribel Von can attack two times on her turn. 

Action Melee Attack: +8 to hit Aribel Von may attack any enemies once if they are within 10 feet of her dealing 7 3d6+3 bludgeoning damage.  

Lophophore Blade: +8 to hit Aribel Von manifest a smoking black blade from one of her tendrils dealing 16 3d10 bludgeoning damage. 

Tendril lash: +8 to hit Aribel Von may attack once more with her tendrils at a creature within 5 feet of her dealing 1d6+3 bludgeoning damage. 

Reaction: +8 to hit When an enemy within 120 feet of Aribel makes a ranged attack on her she may lash out with her tendrils and attack them dealing 3d6+1 bludgeoning damage.

Aribel Von has 3 legendary actions she can take.

Lophophore Vortex (Costs 2): Von extends her tendrils outwards as far away from her as she can and grapples all creatures within 60 feet of her. All creatures within this range must make a DC 19 Strength saving throw or be pulled to within 5 feet of her. If they cannot move to a space within 5 feet of her due to an obstruction, they and the obstruction take 6d4 force damage but are no longer grappled, and are placed within five feet of the obstruction. If the obstruction was a grappled creature, that creature is no longer grappled. 

Lophophore (Cost 1): All creatures grappled by Aribel Von must make a DC 15 Con save as Aribel Von begins draining them of their vitality dealing 1d6 necrotic damage or half as much on a success. The total damage dealt is then returned to Aribel as hit points.