Bulatl

Innate Spellcasting.  The bulatl's spellcasting ability is Charisma (spell save DC 17).  It can innately cast the following spells, requiring only verbal components:
At will: detect evil and good, detect magic, detect thoughts, shield 
3/day each: bless, create food and water, cure wounds, lesser restoration, protection from poison, sanctuary
1/day each: dream, greater restoration, scrying 
Magic Weapons.  The bulatl's weapon attacks are magical.
Shielded Mind.  The bulatl is immune to scrying and to any effect that would sense its emotions, read its thoughts, or detect its location. 
Standing Leap.  The bulatl's long jump is up to 30 feet and its high jump is up to 15 feet, with or without a running start. 
Summon Genies (1/Day).  As an action, the bulatl can magically summon 2 (1d4) bright pink dao to unoccupied spaces on the ground within 15 feet of it.  Summoned dao remain for 1 hour, until they die, or until the bulatl dismisses them as an action.  They are under the bulatl's control, they act on its turn, and it can telepathically command them at any time. 

Multiattack.  The bulatl makes one bite attack and uses its constrict. 
Bite.  Melee Weapon Attack: +10 to hit, reach 5 ft., one creature.  Hit: 31 (4d12 + 5) piercing damage, and the target must succeed on a DC 18 Constitution saving throw or be poisoned for 24 hours.  Until this poison ends, the target is unconscious.  Another creature can use an action to shake the target awake.
Constrict.  Melee Weapon Attack: +10 to hit, reach 10 ft., one Large or smaller creature.  Hit: 12 (2d6 + 5) bludgeoning damage, and the target is grappled (escape DC 18).  Until this grapple ends, the target is restrained, and the bulatl can't constrict another target. 
Change Shape.  The bulatl magically polymorphs into a humanoid or beast that has a challenge rating equal to or less than its own, or back into its true form.  It reverts to its true form if it dies.  Any equipment it is wearing or carrying is absorbed or borne by the new form (the bulatl's choice).

In a new form, the bulatl retains its game statistics and ability to speak, but its AC, movement modes, Strength, Dexterity, and other actions are replaced by those of the new form, and it gains any statistics and capabilities (except class features, legendary actions, and lair actions) that the new form has but that it lacks.  If the new form has a bite attack, the bulatl can use its bite in that form. 
Deadly Leap.  If the bulatl jumps at least 15 feet as part of its movement, it can then use this action to land on its feet in a space that contains one or more other creatures.  Each of those creatures must succeed on a DC 18 Strength or Dexterity saving throw (target's choice) or be knocked prone and take 15 (3d6 + 5) bludgeoning damage plus 15 (3d6 + 5) slashing damage.  On a successful save, the creature takes only half the damage, isn't knocked prone, and is pushed 5 feet out of the bulatl's space into an unoccupied space of the creature's choice.  If no unoccupied space is within range, the creature instead falls prone in the bulatl's space.