Multiattack

The shadow of death can use Vision of Ending. It then makes three shortsword attacks.

Shortsword

Melee Weapon Attack: +15 to hit, reach 5 ft., one target. Hit: 15 (2d6 + 8) piercing damage plus 10 (3d6) necrotic damage.

Vision of Ending

Each creature that is not undead within 60 feet of the shadow of death that can see it must succeed on a DC 22 Wisdom saving throw or become frightened for 1 minute. While frightened in this way, the creature is also paralyzed as it sees visions of its death. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to this shadow of death's Vision of Ending for the next 24 hours.

Teleport

The shadow of death magically teleports, along with any equipment it is wearing or carrying, up to 120 feet to an unoccupied space it can see.