Homebrew
Turn Immunity. The Aegis Reaper is immune to all effects that turn undead. Incorporeal Movement. The Aegis Reaper can move through other creatures and objects as if they were difficult terrain. It takes 6 1d10 force damage if it ends its turn inside an object. Ethereal Sight. The Aegis Reaper can see 60 feet into the Ethereal Plane when it is on a mortal plane, and vice versa. Soul Tracking. If a creature's soul evades death at the hands of the Aegis Reaper by retreating elsewhere, it immediately knows where the soul has gone, even if it is on a different plane of existence. If it was a spell that legitimately returns a being to life, the hunt is called off. If the target has managed to keep the Aegis Reaper from reaching it, a Desolation Reaper takes over the hunt. Undead Nature. The Aegis Reaper does not need to eat, drink, breathe, or sleep. Deathless Servants. If the Aegis Reaper is reduced to 0 hit points, it rematerializes on the Ethereal Plane immediately. If it was killed by its intended target, a Desolation Reaper is called to hunt the target.
Ethereal Scythe. Melee Weapon Attack: +7 to hit, range 5 ft., one target. Hit: 15 3d6+4 necrotic damage. The target must succeed on a DC 13 Constitution saving throw or its hit point maximum is reduced by an amount equal to the damage taken. This reduction lasts until the target finishes a long rest. The target dies if this effect reduces its hit point maximum to 0. Horrifying Visage. Each non-undead creature within 60 feet of the Aegis Reaper that can see it must succeed on a DC 16 Wisdom saving throw or be frightened for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a target’s saving throw is successful or the effect ends for it, the target is immune to that particular Aegis Reaper’s Horrifying Visage for the next 24 hours. Soul Harvest. The Aegis Reaper targets one creature it can see within 30 feet of it that has 0 hit points and is incapacitated. The target must succeed on a DC 13 Constitution saving throw or die, and the Aegis Reaper harvests the soul. Plane Shift. The Aegis Reaper may transport between the various mortal planes of existence and the Ethereal Plane (or any demiplane therein) at will. They do not have the power to bring the living with them. While in the Ethereal Plane, it can neither affect nor be affected by creatures on any other plane.
Invisibility (Recharge 6). Aegis Reaper becomes invisible as per Invisibility.