Heartstop (5e Spell)
From D&D Wiki
|Casting time:||1 action|
|Duration:||Concentration, up to 1 minute|
You point your finger at a huge or smaller creature in range and command its heart to be still. The target must make a constitution saving throw. On a failure, the target’s heart stops beating.
While its heart is stopped, the target is stunned and gains 2 levels of exhaustion at the end of its turn, and it cannot regain hit points for the duration. If the target reaches an exhaustion level of 4 or more while under the effects of this spell, they become unconscious instead of stunned. If the target takes lightning damage during the duration, you must make a constitution save to maintain concentration.
If you break concentration or dismiss the spell as an action, the target’s heart starts beating again, though it will not automatically regain consciousness if unconscious. This spell has no effect on undead, constructs or any other creature that does not require a beating heart to survive. If the target has more than one functioning heart, it is incapacitated instead of stunned, gains 1 level of exhaustion per turn instead of 2, and its exhaustion level cannot be brought above 5 by this spell.