Crysa Thul, The Undead Fetal Diety

Siphon Healing. Crysa Thul siphons the effects of any healing spells targeted at an enemy and has the spell target them instead.

Unearthly Movement. Crysa Thul does not provoke opportunity attacks and can move on any surface, difficult terrain does not affect them.

Umbilical Vitality. At the Beginning of every turn Crysa Thul heals 2 HP

Spellcasting. Crysa Thul is a 4th-level spellcaster. Its spellcasting ability is wisdom (spell save DC 15, +5 to hit with spell attacks). Crysa Thul has following spells prepared:  
Cantrips (at will): Toll the Dead, Chill Touch, Thaumaturgy 
1st level (4 slots): Bane, Inflict Wounds, Ray of Sickness

2nd level (3 slots): Ray of Enfeeblement, Blindness/Deafness, Hold person

Horrid Wail. Crysa Thul screams out, any creature within 20 feet of them makes a WIS save(DC 15) or they are forced to attack their nearest ally. Effected must attack with their most powerful spells and as many abilities as possible.

Corrupting Touch. Melee Weapon Attack: +2 hit, reach 5 ft., 1 target. Hit: 1d4+4 necrotic damage.

Umbilical Whip(Recharge 5-6). Ranged Weapon Attack: +2 to hit, range 10ft., 1target. Hit:  1d8 + 2 necrotic damage. STR save or grappled by Crysa Thul every subsequent turn the grappled can make a wisdom save to escape and every one of Crysa Thul's turns it can deal an extra 1d4 bludgeoning damage + 2 acid damage. Crysa Thul heals by the damage it deals while its targets are grappled.

Corded Parry. Adds +5 to AC for the turn that the reaction is taken.

Crysa Thul has 2 legendary actions.

Disgusting Lashing (Costs 1 Action). Crysa Thul uses their Umbilical Whip attack.

 Inky Secretion(Costs 2 Actions). Crysa Thul casts the spell Darkness. They can also use one legendary action to dismiss this darkness