Cordelia Proudwind

Cordelia Proudwind is a member of the Royal Assembly and is the advisor on occult affairs.
Behind the curtains, Cordelia plans to usurp the king, Ulfric Ionus Ignatius II, and take the throne for herself, though she does not want to become the king. She simply plans to mind control the king, and if possible, the entire population of Everhold, and eventually Goldmoor.
She is a powerful sorcerer, who gained her powers through The Outsider, whose power she now uses to control others. By completing the Oraculum project, she will be able to control both the king and most of Everhold.
Serving her is a group of other sorcerers who gain their powers through Cordelia, called the Wyrmwood Witches. To help her complete her plot she has also taken to seizing control over a bronze dragon from the mountains nearby called Ekeos.
During the end of the Everhold plotline, Cordelia will transform, taking the form of an Atropal.

Skin black as obsidian. As it breathes a foul smell spreads from its drooling mouth. A disproportionately massive head rests upon its slumped shoulders, holding glassy eyes of burning orange. From its midsection a thick umbilical cord snakes across and through parts of its body, stretching into a black hole where the heart once was. The creature does not walk, it simply hovers above the ground, its dead legs hanging from its wretched body. With a loud, discordant scream its arms stretches out towards you.

Cordelia Proudwind

Medium Human, Neutral Evil

Armor Class 17

Hit Points 84 ( 13d6+39 )

Speed: 30 ft

STR

10
( +0 )

DEX

14
( +2 )

CON

16
( +3 )

INT

18
( +4 )

WIS

16
( +3 )

CHA

20
( +5 )

Saving Throws Str +0; Dex +2; Con +7; Int +8; Wis +3; Cha +9;

Isareth the Awakener by Jason Rainville (MtG)

Senses Darkvision: 120 ft.

Languages Common, Deep Speech, Undercommon

Challenge Rating 10

Proficiency Bonus +4

Cordelia Proudwind is a 13th-level spellcaster. Her spellcasting ability is Charisma (spell save DC 18, +9 to hit with spell attacks). Cordelia the has following sorcerer spells prepared:
At will (3/Day): Grasping Vine
Cantrips (at will): Chill Touch, Mage Hand, Message, Mind Sliver, Minor Illusion, Prestidigitation.
1st level (4 slots): Detect Magic, Mage Armor
2nd level (3 slots): Crown of Madness, Darkness, Mirror Image
3rd level (3 slots): Counterspell, Fly
4th level (3 slots): Dimension Door, Sickening Radiance
5th level (3 slots): Dominate Person, Synaptic Static, Teleportation Circle
6th level (1 slot): Mental Prison, True Seeing
7th level (1 slot): Etherealness, Reverse Gravity

Eyes of the Dark. Cordelia has darkvision with a range of 120 feet. In addition, she knows the Darkness spell, which doesn't count against her number of sorcerer spells known, and she can cast it using 2 sorcery points or by expending a spell slot. If she casts it with sorcery points, she can see through the darkness created by the spell.
Strength of the Grave. When damage reduces Cordelia to 0 hit points, she can make a Charisma saving throw (DC 5 + the damage taken). On a success, she instead drops to 1 hit points. She can't use this feature if she is reduced to 0 hit points by radiant damage or by a critical hit.
After the saving throw succeeds, this feature can't be used again until she finishes a long rest.
Font of Magic. Cordelia has 13 Sorcery points and regains all of them when she finishes a long rest. In addition she can spend her sorcery points in the following ways:

Quickened Spell. When Cordelia casts a spell that has a casting time of 1 action, she can spend 2 sorecery points to change the casting time to 1 bonus action for this casting.

Twinned Spell. When Cordelia casts a spell that targets only one creature and doesn't have a range of self, she can spend a number of sorcery points equal to the spell's level to target a second creature in range with the same spell (1 sorcery point if the spell is a cantrip). To be eligible, a spell must be incapable of targeting more than one creature at the spell's current level.

Actions

Thornstrike. Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 12 ( 2d6+ ) piercing damage.
Shadow Walk (Bonus Action). When Cordelia is in dim light or darkness she can, as a bonus action, magically teleport up to 120 feet to an unoccupied space she can see that is also in dim light or darkness.