Agatha Toestealer

Amphibious. The hag can breathe air and water.

Horrific Appearance. Any humanoid that starts its turn within 30 feet of the hag and can see the hag's true form must make a DC 15 Wisdom saving throw. On a failed save, the creature is frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, with disadvantage if the hag is within line of sight, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the hag's Horrific Appearance for the next 24 hours.

Unless the target is surprised or the revelation of the hag's true form is sudden, the target can avert its eyes and avoid making the initial saving throw. Until the start of its next turn, a creature that averts its eyes has disadvantage on attack rolls against the hag.

Create thick moist air. with a snap of her fingers Agatha can make the air around her thick and moist. The effect Is much stronger the closer you get to her

Shapechange. Agatha can slide between forms as easily as average mortals change clothes, assuming any form she pleases. She retains all abilities in these forms. 

Claws. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 17 (4d6 + 7) slashing damage.

Death Glare. The hag targets one frightened creature she can see within 30 feet of her. If the target can see the hag, it must succeed on a DC 10 Wisdom saving throw against this magic or drop to 0 hit points.

Illusory Appearance. The hag covers herself and anything she is wearing or carrying with a magical illusion that makes her look like an ugly creature of her general size and humanoid shape. The effect ends if the hag takes a bonus action to end it or if she dies.

The changes wrought by this effect fail to hold up to physical inspection. For example, the hag could appear to have no claws, but someone touching her hand might feel the claws. Otherwise, a creature must take an action to visually inspect the illusion and succeed on a DC 16 Intelligence (Investigation) check to discern that the hag is disguised.

Spellcasting. Agatha s a 9th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 16, +6 to hit with spell attacks). Agatha has the following hag spells prepared:

 Cantrips (at will): poison spray, toll the dead, mage hand, prestidigitation, suggestion

1st level (5 slots): detect magic, sleep, magic missile, shield

2nd level (5 slots): magic mouth, detect thoughts, hold person, darkness 

 3rd level (3 slots): counterspell, fly, fireball

 4th level (3 slots): greater invisibility, blight, dispell magic

5th level (2 slots): Geas, Modify Memory

6th level (1 slot): Mass Suggestion

Musty Step. surrounded by a stinky green mist, you teleport up to 30 feet to an unoccupied space that you can see. 

Counter spell: You attempt to interrupt a creature in the process of casting a spell. If the creature is casting a spell of 3rd level or lower, its spell fails and has no effect. If it is casting a spell of 4th level or higher, make an ability check using your charisma modifier. The DC equals 10 + the spell's level. On a success, the creature's spell fails and has no effect.

Agatha can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. The night hag regains spent legendary actions at the start of its turn.

Legendary Resistance. Agatha can use legendary resistance 1 time a day

Move. Agatha moves up to its speed without provoking attacks of opportunity.

Attack. Agatha makes one claw attack.

Create Insanity Sphere (Costs 2 Actions). The first time Agatha uses this ability, it creates a 20-foot radius sphere of swirling air centered on a point she can see within 150 feet which remains for 1 minute.  Each creature in the sphere when it appears or that ends its turn there must make a Constitution saving throw or take 2d6 psychic damage. The sphere’s space is difficult terrain.

Until the effect ends, Agatha can use her bonus action on each of its turns to cause a blast of enervating energy to leap from the center of the sphere toward one creature she chooses within 60 feet of the center. She must make a ranged spell attack (+11 to hit). She has advantage on the attack roll if the target is in the sphere. On a hit, the target takes 4d6 psychic damage.

Creatures within 30 feet of the sphere have disadvantage on Wisdom (Perception) checks made to listen.

Move Insanity Sphere (Costs 2 Actions). The night hag can move the death sphere 30 feet.