Aqueix

Immutable Form. The Aqueix can not have its for m changed by any external means such as a polymorph spell. 

Reincarnation. Should the Aqueix die it will return to life in 1d6. The Aquiex resurrects with half health. The Aqueix will reincarnate in the nearest body of water.  

Innate Spellcasting. The Aqueix spellcasting ability is Charisma (spell save DC 14). The Aqueix has following spells prepared:
Cantrips (at will): Ray of Frost
1st level (4 slots): Healing Word, Bless

2nd level(2 slots): Enthrall, Blur

3/day: Control Water

2/day: Cone of Cold,

1/day: Freezing Sphere

Aqueousence. The Aqueix has a naturally liquid form giving it advantage on saving throws, attacks,  and dexterity checks while immersed in a body of water. The aqueix can also sense living creatures within a 60ft radius that are in the same body of water. 

Multiattack. The Aqueix can make two attacks per turn.

Beak. Melee Weapon Attack: +4 to hit, reach 5ft., one target. Hit: 7 (1d8 + 3) Piercing damage. 

Talons. Melee Weapon Attack +4 to hit, reach 5ft, one target. Hit: 15 (3d6 +4) Slashing damage. The target must also make an opposed Dexterity check to avoid being Restrained by the talons.

Screech. The Aqueix releases a high pitched screech that stuns enemies. Any creature within 100ft that is capable of hearing must make a DC 17 constitution saving throw. On a failed save the creature is stunned for 1 round and takes 3d10 thunder damage. On a successful save the creature is not stunned and only takes half damage. 

Imprison. Ranged Weapon Attack +10 to hit, reach 60ft., one target. Hit 22 (5d4 + 10) bludgeoning damage. The Aqueix launches a surge of water that imprisons a single target. If the attack hits the target must make a DC 15 dexterity saving throw to avoid being restrained. The target must make a DC 12 + # of turns of being imprisoned, constitution saving throw to each turn to avoid going unconscious. Only one target can be imprisoned at a time. 

Envelop. Upon taking melee damage the Aqueix can make an opposed Strength check against the attacker. If successful the attacker is pulled inside of the Aqueix liquid form where they are Restrained until they can succeed on a DC 11 strength saving throw (one attempt per turn). Until the attacker is freed they will take 1d4 bludgeoning damage at the beginning of every turn. After 3 turns the attacker will also need to make a DC 13 Constitution saving throw to not become incapacitated every turn they remain trapped unless they can breathe underwater. 

The Aqueix can take 3 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. The Aqueix regains spent legendary actions at the start of its turn. 

Move. The Aqueix takes on a gaseous form and can use its movement without taking any attacks of opportunity. 

Heal Self. The Aqueix regains health equal to 14 (2d8 + 5)

Strong Currents. Release a powerful pulse of water that pushes enemies adjacent enemies back. Enemies that can succeed on a DC 14 strength check are only pushed back 15ft.