Multiattack

Two Shortswords and one Void Tendril attack.

Shortsword

Melee Weapon Attack: +7 to hit, 5 ft., one target, 7 (1d6+4) piercing damage + 3 (1d6) cold and 3 (1d6) force.

Void Tendril

Melee Weapon Attack: +7 to hit, 10 ft., one target, 7 (2d6) bludgeoning damage + 3 (1d6) cold and 3 (1d6) force. Target must make DC 15 Con save or its hp max is reduced by the amount equal to the damage taken. This reduction lasts until target finishes a long rest. Target dies if this reduces its hp max to 0.

Void Speech Rant (Recharge 5-6)

Spews a tirade of Void Speech. Each creature within 40' of it that can hear the tirade: 27 (5d10) psychic and is incapacitated until the end of its next turn (DC 15 Wis half damage and isn't incapacitated).