Ursula The Sea Witch

Legendary Resistance (3/Day). If Ursula fails a saving throw, it can choose to succeed instead.

Amphibious. Ursula can breathe air and water.

Freedom of Movement. Ursula ignores difficult terrain, and magical effects can't reduce its speed or cause her to be restrained. She can spend 5 feet of movement to escape from nonmagical restraints or being grappled.

The Necklace of Nautilus. The symbol of Ursula's power and the mark all of those under her packs bear somewhere on their person. The necklace acts as Ursula's spellcasting focus. It grants her a +2 to her Spell Attack, Spell DC, and AC. Additionally, when a character is affected by a status effect by one of Ursula's spells she may choose to make that effect permanent. The affected character no longer receives saving throws to end the effect and nothing short of a Heal or a greater spell will end the condition on them until the Necklace is destroyed or releases the effect. The Nautilus necklace glows brightly while it is holding this effect in place and may only hold one at a time and it may only affect one creature even if the spell cast affected multiple creatures at once. 

 Master Orator. Ursula is known as the Sea Witch a being of terrifying might, yet there are still many who flock to her call despite the many warnings of others. Ursula has 7 Bardic inspiration (d12), and cannot roll below a 10 for her Charisma Rolls or Saves.

Multiattack. Ursula makes three tentacle attacks may, each of which it can replace with one use of Fling. She may also cast one spell in addition to these attacks.

Cast a Spell. Spell Atack: +17, Spell DC 25: Ursula May cast a spell from the Bard Spell list. She acts as a 20th-level Bard in terms of spell slots available to her.

Tentacle. Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 20 (3d6 + 10) bludgeoning damage, and the target is grappled (escape DC 18). Until this grapple ends, the target is restrained. Ursula has six tentacles, each of which can grapple one target.

Fling. One Large or smaller object held or creature grappled by Ursula is thrown up to 60 feet in a random direction and knocked prone. If a thrown target strikes a solid surface, the target takes 3 (1d6) bludgeoning damage for every 10 feet it was thrown. If the target is thrown at another creature, that creature must succeed on a DC 18 Dexterity saving throw or take the same damage and be knocked prone.

Lightning Storm. Ursula magically creates three bolts of lightning, each of which can strike a target Ursula can see within 120 feet of it. A target must make a DC 25 Dexterity saving throw, taking 28 (8d6) lightning damage on a failed save, or half as much damage on a successful one. If they fail they must also make a DC 25 Constitution saving throw or become stunned until the end of their next turn.

 Unsettling Word. Ursula can spin words laced with magic that unsettle a creature and cause it to doubt itself. As a bonus action, she can expend one use of her Bardic Inspiration and choose one creature you can see within 60 feet of you. Roll the Bardic Inspiration die. The creature must subtract the number rolled from the next saving throw it makes before the start of her next turn.

Ursula can take 5 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. Ursula regains spent legendary actions at the start of its turn.

Cast Lesser Spell. (Costs 2 Actions): Ursula Casts a spell with a casting time of 1 action or 1 bonus action. The Spell can be of a level no greater than 5th Level.

Tentacle Attack or Fling. Ursula makes one tentacle attack or uses its Fling.

Lightning Storm (Costs 2 Actions). Ursula uses Lightning Storm.

Ink Cloud (Costs 3 Actions). While underwater, Ursula expels an ink cloud in a 60-foot radius. The cloud spreads around corners, and that area is heavily obscured to creatures other than Ursula. Each creature other than Ursual that ends its turn there must succeed on a DC 23 Constitution saving throw, taking 39 (6d12) poison damage on a failed save, or half as much damage on a successful one. A strong current disperses the cloud, which otherwise disappears at the end of Ursula's next turn.