Multiattack

One Bite and two Slams. It can make one Tail in place of its Bite.

Bite

Melee Weapon Attack: +12 to hit, 5 ft., one target, 25 (4d8+7) piercing damage + 11 (2d10) poison.

Slam

Melee Weapon Attack: +12 to hit, 10 ft., one target, 23 (3d10+7) bludgeoning damage.

Tail

Melee Weapon Attack: +12 to hit, 10 ft., one target, 26 (3d12+7) slashing damage. If target is a Large or smaller creature it is grappled (escape DC 18). Until the grapple ends the target is restrained and sovereign can't use its tail on another target.

Consume Soul (Recharge 5-6)

Chooses up to three creatures it can see within 60' of it that are incapacitated or stunned by Deathlights. Each target: 55 (10d10) psychic (DC 18 Wis half). Creature stunned by Deathlights has disadvantage on this save. Sovereign then regains hp equal to half total psychic dealt. A Humanoid slain by this rises 1d4 rounds later as a zombie under sovereign's control unless Humanoid is restored to life or its body is destroyed. Sovereign can have no more than thirty zombies under its control at one time.

Spellcasting (Psionics)

Cha (DC 18) no spell components: At will: detect thoughts mage hand (the hand is invisible)3/day ea: dimension door telekinesis1/day: hallucinatory terrain (as an action)