Children of the Night. Adriana magically calls 4 specters at the start of initiative, and calls 2 more at the start of her turn. The specters obey her mental commands, and take their turn directly after hers. Adriana can sacrifice her specters to perform the following effects;

• (1 Specter) If Adriana would fail a saving throw, she succeeds instead.
• (2 Specters) Adriana dispels a magical effect within 60 feet of herself, as the specters drag it to the negative plane.
• (X Specters) On her turn, Adriana sacrifices any number of specters. She regains 25 hit points for every specter sacrificed this way.

Multiattack. Adriana makes one attack with Unscythe and uses her spellcasting feature.

Unscythe (Vampire Form Only). Melee Weapon Attack: +12 to hit, reach 10 ft., one creature. Hit: 11 (2d6 + 4) slashing damage plus 14 (4d6) necrotic damage. The target’s hit point maximum is reduced by an amount equal to the necrotic damage taken, and Adriana 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 Adriana’s control.

Change Shape. Adriana polymorphs into a Beast, a Humanoid, or an Undead that is Medium, Small, or Tiny, or back into her true form. Her statistics, other than her size, are the same in each form. Any equipment she is wearing or carrying is absorbed or borne by the new form. She reverts to her true form if she dies.

Spellcasting. Adriana is a spellcaster. Her spellcasting ability is Charisma (spell save DC 20, +12 to hit with spell attacks). Adriana has the following spells prepared:

Cantrips (at will): chill touch (17th level), mage hand, prestidigitation

1st level (4 slots): detect magic, magic missile, shield

2nd level (3 slots): misty step, suggestion

3rd level (3 slots): animate dead, counterspell, spirit guardians

4th level (3 slots): greater invisibility, ice storm, locate creature

5th level (1 slot): cone of cold, raise dead

Dread Curse. Adriana targets a creature she can see within 60 feet of herself. The target must make a DC 18 Charisma saving throw or become cursed until magic such as Remove curse cast at 5th level or a Greater Restoration spell is used to remove it. While cursed, the target is blinded, and suffers an additional effect whenever the target takes a short or long rest, filling the target's thoughts with horrible images and dreams. The cursed target gains no benefit from finishing a short or long rest. While a target is cursed, Adriana can use the Scrying spell on that creature at will with no components. Only one creature can be cursed in this way at a time. If a new creature becomes cursed in this way, the original target becomes no longer cursed.

Ethereal Step. Adriana can travel between the Ethereal plane and the Material plane. Additionally, if Adriana is reduced to 0 hit points while on the Material plane, she immediately returns to the Ethereal plane and regains 1 hit point. 

Adriana has 3 legendary actions, each activating at the end of another creature's turn. Each legendary action can only activate on a designated round. If the round 3 action is activated, Adriana starts again from the round 1 action.

Dark Ascension (Round 1). Adriana teleports 80 feet into the air and hovers in place until she teleports back to the ground at the start of her next turn. Each specter under Adriana's control can then use their reaction to either move up to its movement without provoking opportunity attacks, or to make a single attack against a target.

Rise! (Round 2). Adriana calls forth more specters. 4 specters appear in spaces Adriana chooses. Each specter then reduces the speed of each hostile creature within 5 feet of it by 10 feet.

Hateful Dead (Round 3). Adriana commands her specters. Each specter under her control uses its reaction to make two attacks with advantage.