Sea fury

A sea fury is a powerful sea hag who sacrificed their kin to enhance their abilities. This subrace is a custom variation on the sea hag created by Matthew Mercer.

Description
When sea hags form a massive coven, growing in magic power to defend themselves from the outside threats, they become too interanly flugitive. One hag, that's stands up above the rest, massacres its kin to siphon their magical power, becoming a sea fury. Driven to madness by the newfound strength and loneliness, a sea fury hoards treasure, spreads rumors, and aims to lure adventurers to its lair, playing with them in hopes to alleviate its loneliness, then ending their lifes when they exhausted their usefullness.

Appearance
A sea fury named Dashilla had aqua green skin and a bulbous, unnaturally proportioned form with long claws. Her long dark hair often fell across much of her face, which had no nose, a mouth full of protruding angler fish-like teeth, and two yellow eyes.

Abilities
Sea furies are immune to cold, fire, poison, bludgeoning, piercing, slashing nonmagical attacks that aren't silvered and immune to paralyzed, poisoned conditions. They have resistance against magic, meaning sea furies have advantage on their saving throws against spells and other magical effects.


 * Innate Spellcasting: The sea fury's innate spellcasting ability is Charisma (spell save DC 16, +8 to hit with spell attacks). It can innately cast the following spells, requiring no material components:
 * At will: Witch Bolt
 * l/day each: Bestow Curse, Fear, Thunderwave
 * Multiattack: The sea fury makes two attacks with its claws.
 * Death Glare: The sea fury targets one frightened creature it can see within 30 feet of it. The target must succeed on a DC 16 Wisdom save or drop to 0 hit points.

Legendary abilities
 * Legendary resistance (3/Day): If the sea fury fails a saving throw, it can choose to succeed instead.
 * Legendary actions (3/round)
 * The sea fury transforms into a wave of foaming seawater, along with whatever it is wearing or carrying, and moves up to its speed without provoking opportunity attacks. While in this form, it can't be grappled or restrained. It reverts to its true form at the end of this movement.
 * Fearsome Apparition (costs 2 actions): The sea fury conjures an apparition of one of its dead sisters, which appears in an unoccupied space the sea fury can see within 30 feet of it. Enemies of the sea fury that can see the apparition must succeed on a DC 16 Wisdom saving throw or be frightened of it until it vanishes at the end of the sea fury's next turn.
 * Conjure Snakes (costs 3 actions): The sea fury disgorges a swarm of poisonous snakes, which occupies the same space as the sea fury, acts on its own initiative count, and attacks as directed by the sea fury. The sea fury can control up to three of these swarms at a time.

Regonal effects
 * Sea water within 5 miles of the lair becomes coarse and choppy, as if whipped by an unseen wind.
 * Sea grass within 1 mile of the lair is imbued with a foul mockery of life, grasping ineffectually at any creature that passes within 5 feet of it.
 * Ordinary crabs and octopi within 1 mile of the lair grow in size to become giant crabs and giant octopi. These creatures serve the sea fury as spies and guards.

Lair actions
 * Water within 120 feet of the sea fury become foggy or murky, to the extent that the area becomes heavily obscured.
 * The sea fury conjures a 15-foot cube of water that fills an unoccupied space it can see within 30 feet of it, then moves the water in a straight line up to 60 feet, after which the water disperses. Any creature that comes into contact with the rushing wave must succeed on a DC 16 Strength saving throw or be knocked prone by it and pushed 15 feet along its course.
 * The sea fury calls forth the spirit of a dead sailor or sea hag that met its end in the lair. This spirit has the statistics of a specter and lasts until the sea fury uses another lair action. The specter appears in an unoccupied space within 30 feet of the sea fury and obeys the sea fury's commands.

Known sea furies

 * Dashilla the Dreadful: Dashilla occupies her lair in the Diver's Grave, which lies at the bottom of the Lucidian Ocean, southwest of Bisaft Isle.

The Mighty Nein encountered Dashilla while exploring the Diver's Grave in search of a Cloven Crystal; the sea fury was able to escape with her life and hide in the depths of her lair.

The Nein then found a pile of merrow bodies and discovered the pedestal in her central lair had runes that lit up when they absorbed a sufficient quantity of blood.

Trivia

 * The sea hag's and sea fury's Death Glare ability is similar to the Death Gaze of a bodak.