Arnos Sonra

Legendary Resistance (3/day). If Arnos fails a saving throw, he can choose to succeed instead..

Spellcasting. [Arnos Sonra] is a 9th-level spellcaster. His spellcasting ability is [Charisma] (spell save DC 18, +10 to hit with spell attacks). [Arnos Sonra] has the following [Sorcerer] spells prepared:
Cantrips (at will): Chill Touch, Prestidigitation, True Strike  
1st level (4 slots): Mage Armor, False Life, Witch Bolt, Detect Magic
2nd level (3 slots): Detect Thoughts, Enhance Ability, Blur
3rd level (3 slots): Counterspell, Lightning Bolt, Protection From Energy
4th level (3 slots): Banishment, Greater Invisibility 
5th level (1 slot): Animate Objects 

Misty Escape. When Arnos drops to 0 hit points, he transforms into a cloud of mist (detail in shapechanger) instead of falling unconscious, providing that he isn't in sunlight or running water. If he can't transform, he is destroyed.

Regeneration. Arnos regains 25 hit points at the start of his turn, as long as he has at least 1 hit point and isn't in sunlight, running water or if he took radiant damage or damage from holy water at the start of his next turn.

Spider Climb. Arnos can climb difficult surfaces, without needing to make an ability check.

Charm. Arnos targets a humanoid he can see within 30ft. If the target can see him, the target must succeed on a DC 18 [Charisma] saving throw against this magic or be charmed by him. This effect lasts for 24 hours unless the target is attacked by Arnos or any of his companions if this happens the target may repeat the save.

Multiattack. Arnos makes two attacks only one of which can be a bite attack

Unarmed Strike. Melee Weapon Attack: +9 to hit, reach 5 ft., 1 target. Hit: 8 (1d8 + 4) [Bludgeoning] damage, Instead of dealing damage Arnos can choose to grapple on a successful hit instead (DC 18 Athletics to escape). 

Bite. Melee Weapon Attack: +9 to hit, reach 5ft, one willing creature or creature that is Grappled by Arnos, Incapacitated or Restrained. Hit: 7 (1d6 + 4) piercing damage plus 10 (3d6) Necrotic Damage. The targets hit point maximum is reduced by an amount equal to the necrotic damage taken, and Arnos regains hit points equal to that amount. The reduction lasts until the target finishes a Long Rest. The Target dies is this effect reduces it's hit point maximum to 0. A humanoid slain in this way and then buried in to the ground rises the following night as a [Vampire Spawn] under Arnos Sonra's control.

Crimson Slither. Melee Weapon Attack: +12 to hit, reach 5ft, 1 target, Hit: 9(1d8 + 7) plus (2d6) Necrotic damage.

Alpha call (1/ day). Arnos magically summons (2d6) wolves to his side, they arrive the turn they are summoned and remain for 1 hour, until Arnos dies or he dismisses them as a Bonus Action.

Arnos can take 3 legendary action, all spent points are regained when he ends his turn.

Move (Costs 1 Action). Can move with provoking opportunity attacks.

Shapechanger (Costs 1 Action). If Arnos isn't in sunlight or running water, he can use his action to polymorph into a (medium sized) cloud of mist or back into its true form. Whilst in mist form, Arnos can't take any actions, speak or manipulate objects. He is weightless, has a flying speed of 20ft, can hover, and can enter a hostile creatures space and stop there. In addition, if air can pass through a space the mist can do so without squeezing, it cannot pass through water, it has advantage on all Str, Dex and Con saving throughs and resistance to all non-magical damage except sunlight.

Bite (Costs 2 Actions). Make one bite attack.