Ainz Ooal Gown

Special Equipment. Ainz carries the Guildmasters staff. While holding the staff, he can expend 1+ spell level charges to cast a spell that he has prepared without expending a spell slot. Additionally, every undead creature he chooses that he can see gains 20 temp hit points. An undead can only benefit from this effect once every 24 hours

Legendary Resistance (7/Day). If Ainz fails a saving throw, he can choose to succeed instead. 

Limited magic immunity. Unless he wished to be affected, Ainz is immune to spells of 6th level or lower. He also has advantage on saving throws against all other spells and magical effects. This ability persists until Ainz expends his last use of legendary resistance                                                   

Spellcasting. The Ainz Ooal Gown is a 20-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 27, +19 to hit with spell attacks). The Ainz Ooal Gown has following  spells prepared:
Cantrips (at will): message, acid splash, toll of the dead, fire bolt, friends
1st level (at will): magic missile, ray of sickness, shield                                                              2nd level (at will): arcane lock, knock, dragon's breath, ,melf's acid arrow                              3rd level (at will): animate dead, dispel magic, fireball, fly, lightning bolt, tongues                4th level ( 4 slots): blight, greater invisibility, ice storm, phantasmal killer, storm sphere    5th level (4 slots): cloudkill, conjure elemental, flame strike, hold monster, immonlation, wall of force                                                                                                                                         6th level (4 slots): chain lightning, circle of death, create undead, disintegrate                     7th level (4 slots): finger of death, plane shift, teleport, mordenkainen's magnificent mansion                                                                                                                                              8th level (3 slots): Dominate monster, mind blank                                                                      9th level (3 slots): power word kill, time stop, meteor swarm 

Superior mind: Ainz can maintain concentration on two different spells at the same time. In addition, he has advantage on saving throws to maintain concentration on spells

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

Action Name. Enter the description for your action.

paralyzing touch. Melee spell attack: +12 to hit, reach: 5ft. one creature. Hit: 24 (3d6+12) cold damage, and the target must succeed on a DC 27 constitution saving throw or be paralyzed for 1min. The target can repeat the saving throw at the end of each of it's turns, ending the effect on itself on success.

Staff. Melee weapon attack:+12 to hit, reach 5ft. one target. Hit: 7(1d6+3) bludbeoning damage plus 12(3d6) necrotic damage, or 8(1d8+3) bludgeoning damage plus 12(3d6) necrotic damage when used with two hands 

Enter the description for how legendary actions work for your monster here.

At-Will Spell. Ainz casts on of his at will spells                                                                          Melee Attack. Ainz uses paralyzing touch or makes one melee attack with his staff         Maximize Magic (2 actions). Ainz empowers the next 5th level or lower spell he casts, gaining advantage on any attack roll, causing creatures to have disadvantage on any saving throw, and treating any damage dice as having rolled their maximum values. This affect persists until the spell ends                                                                                      Fallen down (3 actions). Ainz decimates a 60ft. radius, 500ft, high area centered around him. Each creature and object in the area must make a DC 27 Constitution saving throw, taking 31(7d8) radiant damage and 31(7d8) fire damage on a failed save, or half as much damage on a successful one.                                                                            Summon Servant (3 actions), Ainz summons a CR 10 or lower elemental fiend, or undead up to 15ft away at a location he can see. The servant rolls its own initiative, lacks legendary actions, and fights for Ainz until it is slain. Ainz can have up to 3 servants. summond in this way active at any time. The servants are unsummoned if Ainz falls to 0 hit points , or after 24 hours 

Enter the description for how mythic actions work for your monster here.

Mythic Action Name (Costs # Actions). Enter the description for your mythic action.