Branwen Tempest, Ancient Witch

You played around, hoping to find some natural magic within you.  All the teens do it, once or twice, hoping to discover that they have fantastical abilities that will make their lives into something.  Who wants to be a farm hand or a milk maid all their lives?  Only you had an edge over all those other wannabe's, because you found that ragged book in the old attic you were told to clean out.  You couldn't read the words, but they seemed to hold some kind of power.  The drawings certainly looked like something magic.  And when the lady of the house asked you to kill a chicken for dinner, you couldn't help but take notice of all the blood, which you caught some of and used it to draw a few of those magic symbols on the floor of your bedroom that night.  And sure enough they began to glow, but when the smoke started to gather and quickly fill the room, you panicked and started for the window.  Then out of the smoke, she stepped into the room, a woman so beautiful you couldn't help but pause.  With but a smile, and an offer to give you the magic you craved, you gladly knelt before her as she took your hand in hers.  Then you noticed her reflection in the mirror, a grotesque hag so ugly you nearly screamed.  Before you could pull away, however, she had her dagger out and was sliding its blade across the palm of your hand, and your blood was dripping onto the glowing symbols you had drawn on the floor.  As the room began to grow darker around you, you could feel your very soul binding with that of the creature standing before you.  As the darkness overcame you, she spoke, her voice now ancient and foreboding.  "The Bond is made!  Welcome to the Coven . . . my pretty."  The last you can remember is her laugh, and the way it seemed to make dogs howl and babies cry.

Extended Spell List

The ancient power of the coven now flows through you, enabling you to learn spells that would otherwise be unavailable.

• 1st level - Bane, Entangle, Hideous Laughter
• 2nd level - Blindness/Deafness, Enlarge/Reduce
• 3rd level - Haste, Spirit Guardians
• 4th level - Secret Chest, Polymorph
• 5th level - Cloudkill, Dream

At the very moment your eyes opened again, in the light of the morning sun shining through the window, you could feel the power of the witch coursing through your body.  You already know the cantrips Dancing Lights and Vicious Mockery.  They do not count against your spells known.

Mimicry

At 1st level, you immediately gain one of the witch's abilities.  You find that you can mimic animal sounds and humanoid voices almost perfectly, as long as you have heard the sound or voice yourself.  To succeed, you must roll a Performance check with advantage.  The DC is set by your DM, depending on how familiar your character is with the sound.

Beneath the Surface

At 6th level, you develop another of the witch's abilities.  You gain the ability to physically change your body at will, as if you were casting the spell Alter Self, though you can only create webbing between your fingers and toes, and gill slits at the base of your neck over your collarbones.  In addition to air, you can now breathe under water for a number of minutes equal to either your charisma or constitution modifier.  You must return to the surface and breathe air for at least 30 seconds before you can go under water again.  While altered, you have a swim speed equal to your walking speed.  

The Hag In You

By the time you reach 10th level, your physical appearance has been changing significantly.  Though your charisma is unaffected, because your force of being is growing to outweigh the physical changes, your face and skin are becoming rougher and thicker.  Your hair is thinning significantly and retains a greasy pallor.  Your fingers are growing longer, and your fingernails have become like claws.  Due to these changes, you gain a +1 bonus to your armor class, and add a 4d4 to your unarmed attack.  If you successfully hit someone with your claws, they must make a Constitution saving throw (DC is 5 + your warlock level).  If they fail, they are considered Poisoned until the end of your next turn.  To hide these grotesque changes from those who frighten easily, you can cast a glamor illusion that covers yourself and anything you are wearing or carrying at will.  This illusion will give others the impression that you look like another creature of your general size and humanoid shape. The illusion ends if you take a bonus action to end it.  The changes wrought by this effect fail to hold up to physical inspection.  It will also fail if subjected to an anti-magic field of any kind, and can be seen through by anyone possessing truesight.

The Hag Among Them

At 14th level, you gain the natural ability to turn invisible once per short rest.  This invisibility will last until you end it, until you cast a spell or attack someone, or until your concentration ends (as if concentrating on a spell).  While invisible, you leave no physical evidence of your passage (you can be heard or touched), so you can only be tracked by magic.  Any equipment you wear or carry is invisible with you.