Disolve: If her movement speed is greater than 0 and is not restrained, she can use her movement in incorporial form while she appears as a cloud of red monarch butterflies.

Spellcasting: Zaria is a 10-level spellcaster. Its spellcasting ability is [19] (spell save DC 18, +10 to hit with spell attacks). Zaria has following [Wizadrd, Order of the Profane Soul Bloodhunter] spells prepared:
Cantrips (at will): Eldrich Blast, Chill Touch, Toll the Dead, Mold Earth, Message, Minor Illusion, Mage Hand 
1st level (4 slots & 1 Pact): Armor of Agathys, Arms of Hadar, Cause Fear, Ray of Sickness, Sleep, Witch Bolt
2nd level (3 slots): Blindness/Deafness, Silence, Gentle Repose
3rd level (3 slots): Animate Dead, Bestow Curse, Feigh Death, Spirid Shorud, Summon Undead
4th level (3 slots): Blight, Phantasmal Killer, Summon Greater Demon
5th level (2 slots): Danse Macabre, Enervation
6th level (1 slot): Create Undead
7th level (1 slot): Finger of Death
8th level (1 slot): Abi-Dalzim's Horrid Wilting
9th level (1 slot): Meteor Swarm

Ritual spellcasting: Inprisonment, Clone, Comprehend Languages, Illusory Script, Unseen Servant

Legendary Resistance (3/day): if Zaria fails a saving throw, she can choose to succeed instead.

Banshee screach: Tortured screams of all souls in Domains of Dread channel through the dissloding jaws of Zaria. All living creatures in a 20ft cone must make a Constitution saving throw against Zarias spell save DC and take 10d6 and are petrified until the end of their next turn on a failed save, or take half the damage and are not petrified. Zaria can use this ability once per dawn.

Action Melee Attack: Ghastly Claws: +10 to hit, reach 10 ft., 3 targets Hit: (1d8 + 5) magical slashing damage. If Zaria dealt damage on her turn, she can use her bonus action to make an attack with her Ghastly Claws

Action Ranged Attack: Zaria can cast spells as per her spellcasting

Attack of oportunity: Each creature that moves out of the range of her Ghastly Claws provokes an attack of oportunity

Zaria can take 2 legendary actions, choosing from the options below. Only one legendary action can be used at a time and only at the end of another creature's turn. Zaria regains 1 use of her legendary action at the start of her turn

At-Will Spell (Costs 1 Action): Zaria can cast any of her spells as per her spellcasting

Attack (Costs 1 Action): Zaria can use her Claw attack

Swarm of Worry (Costs 2 Actions): Zaria calls forth all skeletons within 10 mile radius that burrow up from a point within this radius as a singular monster (using the stats of Storm Giant Skelleton). The creature joins initiative and is controlled by Zaria without requiring action or a bonus action.