Dark Gifts
The vestiges sealed in the Amber Temple's vault each offer a gift for a price. Accepting one is permanent. Take the hollow one and Strahd's end may not be yours (Endings).
A Mouth of Borrowed Teeth
Dahlver-Nar, the mouth of borrowed teeth
2 more Hit Points per level, and Advantage on death saving throws. The price: Charisma -2, Disadvantage on Persuasion, and a mouthful of teeth that aren't yours.
The Eyes of Drizlash
Drizlash, who spins between the walls
A 30 ft climbing speed, darkvision 120 ft, and Web a few times a day. The price: Charisma -2, extra eyes that never close, and trouble in sunlight.
Fekre's Fever
Fekre, the mother of fevers
Immunity to poison, and Blight once per long rest. The price: Charisma -2, and every healing spell or potion does you only half its good.
The Backward Stars
Khirad, who reads the stars backward
Advantage on Initiative, +5 to passive Perception, and Clairvoyance once per long rest. The price: 1 fewer Hit Point per level, and visions that never let you rest easy.
The Eraser's Finger
Norganas, the eraser
Finger of Death once per long rest. The price: Intelligence -4, and each casting takes a memory you loved.
The Locked Mouth
Savnok, the locked mouth
You can't be Charmed, and Advantage on Deception. The price: Disadvantage on Persuasion, -5 to passive Perception, and never again a true word about yourself.
The Hounds' Leash
Seriach, master of the burning hounds
Resistance to fire, and your weapon blows burn for an extra 1d6 fire. The price: vulnerability to cold, and beasts that panic at your smell.
The Honeyed Hand
Shami-Amourae, the honeyed hand
Advantage on Persuasion, and Charm Monster once per long rest. The price: Disadvantage on saves against being Charmed, and no will to refuse a pleasure.
The Hollow Belly
Sykane, the hollow belly
Vampiric Touch a few times a day, and resistance to necrotic damage. The price: 1 fewer Hit Point per level, and you can't spend Hit Dice on a day you haven't fed.
The Five Throats
Great Taar Haak, the five-throated war
Strength +4 (up to 22) and 1 more Hit Point per level. The price: Intelligence -2, Disadvantage on Wisdom saves, and a rage that won't stop at surrender.
The Grave Wyrm's Claim
Tarakamedes, the dragon in the grave
Animate Dead and Speak with Dead once per long rest each, and resistance to cold. The price: Disadvantage on every death saving throw.
The Last Shadow
Tenebrous, the last shadow
Darkvision 120 ft, Advantage on Stealth, and Darkness a few times a day. The price: vulnerability to radiant damage.
The Second Thirst
The Thirst, whose name was cut away
Strength and Constitution +2, darkvision, necrotic resistance, a draining strike and more Hit Points. The price: radiant vulnerability, sunlight's burn, and the devil's own thirst.
Yog's Hide
Yog, the unbroken
Resistance to bludgeoning, piercing and slashing damage. The price: Speed -10 ft, Dexterity -2, and no feeling in your skin ever again.
The Outside Eye
Yrrga, the eye that opened outside
Truesight out to 30 ft. The price: Wisdom -2, and Disadvantage on saves against being Frightened, because now you see what's really there.
The Crown of Zantras
Zantras, who crowned beggars
Charisma +4 (up to 22). The price: Disadvantage on Stealth and Insight checks, and a hunger to be the one everyone watches.
The Dead Star's Light
Zhudun, the dead star
Hunger of Hadar once per long rest, and resistance to radiant damage. The price: Constitution -2, vulnerability to fire, and a corpse-light no hood can hide.