Multiattack. Soth makes three Forsaken Brand attacks.

Forsaken Brand. Melee Weapon Attack: +12 to hit, reach 5 ft., one target. Hit: 10 (1d8 + 6) bludgeoning damage plus 18 (4d8) necrotic damage, and if the target is a creature, it can't regain hit points until the start of Soth's next turn.

Cataclysmic Fire (1/Day). Soth hurls a magical ball of fire that explodes at a point he can see within 120 feet of himself. Each creature in a 20-foot-radius sphere centered on that point must make a DC 19 Dexterity saving throw. A creature takes 35 (10d6) fire damage and 35 (10d6) necrotic damage on a failed save, or half as much damage on a successful one. Additionally, any Medium or smaller Humanoid killed by this damage, as well as every corpse of such a creature within the sphere, becomes a skeleton (see the Monster Manual) under Soth's control. The skeleton acts on Soth's initiative but immediately after his turn. Absent any other command, the skeleton tries to kill any non-Undead creature it encounters.

Word of Death (1/Day). Soth points at a creature he can see within 60 feet of himself and magically commands it to die. The target must make a DC 19 Constitution saving throw, taking 100 necrotic damage on a failed save, or half as much damage on a successful one. If this damage reduces the target to 0 hit points, the target dies.

Implacable Maneuver. Soth moves up to his speed or commands a mount he is riding to move up to its speed. The movement from this action doesn't provoke opportunity attacks. If he or his mount moves within 5 feet of a creature during this movement, he can force the creature to make a DC 20 Strength saving throw. The creature is knocked prone unless it succeeds on the saving throw.

Strike (Costs 2 Actions). Soth makes one Forsaken Brand attack.

Cast a Spell (Costs 3 Actions). Soth uses Spellcasting.