Ainz Ooal Gown

Aura of the Overlord. Ainz is surrounded by a 120-ft aura of necromantic magic. Any undead not under Ainz' contraol that ends its turn within the aura must succeed on a DC 21 Charisma saving throw or be charmed by Ainz. Undead Charmed in this way follow any verbal commands issued by Ainz. In addition, any undead that starts its turn in the aura automatically gains 20 temporary hit points.

Despair Aura. Ainz is surrounded by a 40-ft aura of despair. Any creature that starts its turn in the aura or enters it for the first time on its turn must make a DC 21 Wisdom saving throw. On a failed save, the creature is frightened for 1 minute. A frightened creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature fails the save by 10 or more, it is immediately afflicted with madness for 1 minute, and cannot reroll the save until the minute or 10 turns have passed. A creature that succeeds on the saving throw is immune to the effect for 24 hours.

Ring of Free Movement. While wearing this ring, Ainz has advantage on saving throws made to avoid being grappled or restrained.

Ring of Non-Detection. While wearing this ring, Ainz is immune to the effects of any divination spell.

Ring of Three Wishes. This ring has 3 charges. Ainz can use an action and expend a chartge to cast the Wish spell.

Turn Resistance. Ainz has advantage on saving throws against any effect that turns undead.

Natural Leader. Ainz does not need to maintain concentration on summoning spells.

Undead Nature. Ainz does not need to breath, drink, eat, or sleep.

Limited Magic Immunity. Ainz can't be affected or detected by spells of 4th level or lower unless he wishes to be. He has advantage on saving throws against all other spells and magical effects.

Necrotic Absorption. Whenever Ainz is subjected to necrotic damage, he takes no damage and is instead regains a number of hit points equal to the necrotic damage dealt.

Spellcasting. Ainz Ooal Gown is a 22-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 25, +17 to hit with spell attacks). Ainz has following wizard spells prepared:
Cantrips (at will): Acid Splash, Infestation, Message, Minor Illusion, Ray of Frost, Toll the Dead
1st level (5 slots): Magic Missile, Mage Armor, Ray of Sickness, Shield, Tasha's Hideous Laughter
2nd level (4 slots): Blindness/Deafness, Hold Person, Melf's Acid Arrow, Misty Step, Shadow Blade
3rd level (4 slots): Counterspell, Fireball, Fly, Lightning Bolt
4th level (4 slots): Blight, Confusion, Evard's Black Tentacles, Ice Storm
5th level (3 slots): Dominate Person, Enervation, Negative Energy Flood
6th level (3 slots): Chain Lightning, Mental Prison, Scatter
7th level (3 slots): Finger of Death, Power Word Pain, Teleport
8th level (3 slots): Feeblemind, Incendiary Cloud, Power Word Stun
9th Level (2 slots): Power Word Kill, Time Stope

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

Touch of Undeath. Melee Spell Attack: +10 to hit, reach 5 ft., 1 target. Hit: 20 (2d10 + 9) necrotic damage, and the target must make a DC 21 Constitution saving throw or have its Strength score reduced by 1d4 until the next long rest. If a creature's Strength score is reduced to 0 in this way, it becomes paralyzed until it's Strength score becomes 1 or higher.

Animate Dead (10/day). Ainz casts the Animate Dead spell without expending a spell slot.

Create Undead (2/day). Ainz casts the Create Undead spell without expending a spell slot.

Danse Macabre (6/day). Ainz casts the Danse Macabre spell without expending a spell slot.

Staff of Ainz Ooal Gown (7/day). Ainz uses his staff to summon a single elemental of CR 10 or below. The elemental is friendly towards Ainz and his allies, and obeys any verbal commands issued by him. Ainz can only summon each type of elemental once per long rest.

Ainz can take 2 legendary actions. Only one legendary action can be used at a time and only at the end of another creature's turn. Ainz regains spent legendary action at the start of his turn

Summoning (Costs 1 Actions). Ainz may use one of his charges of Animate Dead, Create Undead, or Danse Macabre or use a charge of his staff to summon an elemental after another creature's turn.

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