Umbral Sepulchre

A spell of the dead worlds, words of raw power combine with runes of ill omen to conjure forth true horror, visiting death upon those foolish enough to be within its deadly grasp. When you cast this spell, target up to three creatures within range that you can see. Great clawed hands of shadowstuff extend from the ground, silently dragging victims to their death.

Each target must make a Constitution saving throw or be restrained by the hands and suffer 5d12 necrotic damage at the beginning of their next turn, as well as every turn affected by the spell unless otherwise specified. The creature repeats this saving throw at the end of its next turn; after three successes the spell ends on the creature. After each success the creature does not take the necrotic damage at the start of its next turn, though it remains restrained until the spell ends on it. After three failures (including the first made to avoid the spell), its soul is ripped from its body and the creature dies instantly; creatures lacking souls take 5d12 additional necrotic damage and the spell ends on them after the third failure. The successes or failures need not be consecutive.

As an action while concentrating on this spell, you can force a Constitution saving throw on each creature restrained by this spell. On a failed save the creature suffers 2d12 necrotic damage and you regain hit points equal to the damage done.