Arch dutchess Lilith

Shapechanger. If lillith isn’t in sunlight or running water, it can use its bonus action  to polymorph into a displacer beast it can't cast spells in this form it can do this once per short rest

Mist fourm 

While in mist form, the vampire can’t take any actions, speak, or manipulate objects. It is weightless, has a flying speed of 20 feet, can hover, and can enter a hostile creature’s space and stop there. In addition, if air can pass through a space, the mist can do so without squeezing, and it can’t pass through water. It has advantage on Strength, Dexterity, and Constitution saving throws, and it is immune to all nonmagical damage, except the damage it takes from sunlight.

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

Misty Escape. When it drops to 0 hit points outside its resting place, the vampire transforms into a cloud of mist (as in the Shapechanger trait) instead of falling unconscious, provided that it isn’t in sunlight or running water. If it can’t transform, it is destroyed.

While it has 0 hit points in mist form, it can’t revert to its vampire form, and it must reach its resting place within 2 hours or be destroyed. Once in its resting place, it reverts to its vampire form. It is then paralyzed until it regains at least 1 hit point. After spending 1 hour in its resting place with 0 hit points, it regains 1 hit point.

Sanguine alchemy 

Once per round when Lilith takes damage from a bludgeoning slashing or pearcing damage every creature within 5ft takes 1d6 fire damage. As Lilith blood runs hot as the hells. 

(This ability came to be when Lilith was trying to create a potion that would restore warmth to her undead body once again the experiment failed her blood burns hotter then avernus) 

 Shape change expertise 

lillith gains 1d4 to all attack rolls ability checks and saves when she has taken on the form of another living creature she's studied for at least one day spells like moon beam can force her out of this 

 Alchemical regeneration 

lilith gains 20 temporary hp at the start of her turn aswell as 10hp the the temp hp regains even if she is exposed to sunlight bit the hp does not 

Spell casting lillith is a 12th level spell caster she uses spells from the wizard and bard school she uses a violin as her spell casting bonus her spell save DC 17 and her spell attack is 9 she uses charisma as her spell casting focus 

Fire ball,misty step,magic missile,longstrider,scorching ray,see invisibility,shield,counterspell,fog,hellish rebuke,mage armour, arcane lock,silvery barbs,contagion,find familer 

 True immortality 

If lillith ever actually dies she will revive in 30days within 5ft of one of her legendary tomes if the tomes are destroyed and she is killed in her coffin the normal way you kill a vampire she is truly dead 

Sanguine haste 

You gain an additional bonus action each turn aswell as have advantage in Dexterity saves and checks 

Sanguine spells 

when she casts magic missle it does 2d6 damage per missile 

when she casts blight it deals 8d10 necrotic damage 

when she casts find familer she can summon a psudo dragon she has resistance to spells while this psudo dragon is alive it has 40 hitpoints and gives lillith warding bond 

When she casts fire ball she deals necrotic damage instead and heals half the damage done 

Vampire Weaknesses. The vampire has the following flaws:

Liliths sanguine spells can't be cast when she is in sunlight her sanguine ability's do not function if she has taken at least 20 radiant damage by the end of her next turn 

Forbiddance. The vampire can’t enter a residence without an invitation from one of the occupants.

Harmed by Running Water. The vampire takes 20 acid damage if it ends its turn in running water.

Stake to the Heart. If a piercing weapon made of wood is driven into the vampire’s heart while the vampire is incapacitated in its resting place, the vampire is paralyzed until the stake is removed.

Sunlight Hypersensitivity. The vampire takes 20 radiant damage when it starts its turn in sunlight. While in sunlight, it has disadvantage on attack rolls and ability checks.

Hand crossbow action/bonus action 

1d6+1d10+10 +9 to hit 

Legendary tomes

She posesses three tomes as action she can read from one of her tomes she gains the tomes ability until the end of the day she can only possess one ability at a time 

Tomes of the dead 

Chill touch,inflicts wounds,blight,raise dead you can cast these spells without expending a spell slot they are cast at there lowest level 

 Tomes of the unselie 

The person gains freedom of movement and can turn invisible and teleport up to 60ft without expending a action while in dim light 

Tomes of the profane 

The user gains 100 temp hp and as a action can shoot a eldritch blast that can target up to 4 different creatures and does 2d10 damage 

(Let players know about the tomes power so they don't want to destroy them) 

Multicast once per day lillith can cast 3 spells in one turn she cannot take any action/bonus until the end of her next turn (This damages the weave and angers the gods) 

Unarmed Strike (Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one creature. Hit: 8 (1d8 + 4) bludgeoning damage. Instead of dealing damage, the vampire can grapple the target (escape DC 18).

Bite. (Bat or Vampire Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one willing creature, or a creature that is grappled by the vampire, incapacitated, or restrained. Hit: 7 (1d6 + 4) piercing damage plus 10 (3d6) necrotic damage. The target’s hit point maximum is reduced by an amount equal to the necrotic damage taken, and the vampire regains hit points equal to that amount. The reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hit point maximum to 0. A humanoid slain in this way and then buried in the ground rises the following night as a vampire spawn under the vampire’s control.

Charm. The vampire targets one humanoid it can see within 30 feet of it. If the target can see the vampire, the target must succeed on a DC 17 Wisdom saving throw against this magic or be charmed by the vampire. The charmed target regards the vampire as a trusted friend to be heeded and protected. Although the target isn’t under the vampire’s control, it takes the vampire’s requests or actions in the most favorable way it can, and it is a willing target for the vampire’s bite attack.

Each time the vampire or the vampire’s companions do anything harmful to the target, it can repeat the saving throw, ending the effect on itself on a success. Otherwise, the effect lasts 24 hours or until the vampire is destroyed, is on a different plane of existence than the target, or takes a bonus action to end the effect.

Children of the Night (1/Day). The vampire magically calls 2d4 swarms of bats or rats, provided that the sun isn’t up. While outdoors, the vampire can call 3d6 wolves instead. The called creatures arrive in 1d4 rounds, acting as allies of the vampire and obeying its spoken commands. The beasts remain for 1 hour, until the vampire dies, or until the vampire dismisses them as a bonus action.

Cunning action 

Lilliths counter spell Spells of level one and 2 can be countered if countered this way she may cast the spell as a legendary action.

Shape changer Lilith at any point can take the fourm of another humanoid the human has to be female her clothes change and her distinct flaming eyes are hidden but her touch is uncomfortabley hot.

The vampire can take 3 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. The vampire regains spent legendary actions at the start of its turn.

Move. The vampire moves up to its speed without provoking opportunity attacks.

Unarmed Strike. The vampire makes one unarmed strike.

Bite (Costs 2 Actions). The vampire makes one bite attack.

liliths counterspell cast the spell countered by lilliths counterspell