Warchief Thrall

Legendary Resistance(3/Day). If Warchief Thrall fails a saving throw, he can choose to succeed instead.

Special Equipment. Thrall is equipped with Doomhammer and Robes of the Archmagi (already added to AC and Spell Save DC/Attack modifier.

Magic Resistance. Thrall has advantage on saving throws against spells and other magical effects.

Summon Spirit Wolves. As an action Thrall may summon 2 Spirit Wolves to aid in battle, lasts 1 hour or until killed or Dismissed.

Spellcasting. Warchief Tharr is a 18th level spellcaster. Its spellcasting ability is Wisdom (spell save DC 19, +11 to hit with spell attacks). Warchief Thrall has following Sorcerer spells prepared:

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Cantrips (at will): Thunderclap, Mold Earth, Lightning Lure, Frostbite

1st level (4 slots): Thunderwave, Shield, Charm Person, Chromatic Orb

2nd level (3 slots): Hold Person, Invisibility, Shatter, See Invisibility

3rd level (3 slots): Counterspell, Dispell Magic, Lightning Bolt 

4th level (3 slots): Banishment, Polymorph, Confusion

5th level (3 slots): Cone of Cold, Dominate Person, Far Step

6th level (1 slot): Chain Lightning

7th level (1 slot): Teleport

8th level (1 slot): Power Word Stun

9th level (1 slot): Mass Polymorph

Multi attack. Thrall may attack 3 times with Doomhammer.

Doomhammer. Melee Weapon Attack: +9 to hit, reach 5 ft., 1 target. Hit: 8/10 (1d8/1d10 + 5) Bludgeoning damage.

Warchief Thrall can take 3 legendary actions, choosing from the actions below. Only one legendary action option can be used at a time and only at the end of another creatures turn. Warchief Thrall regains spent legendary actions at the start of his turn..

Cantrip or level 1 spell (Costs 1 Action). Thrall casts a level 1 spell of a cantrip.

Doomhammer (Costs 1 Action) Thrall may attack twice with Doomhammer.

Command (Costs 2 Actions) Thrall encourages his spirit Wolves to attack an enemy.