Essence of Lifespark (5e Spell)
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You restore or take away the very essence of a target. You speak an Utterance that forcibly restores life to a target whose personal Truename you know by weaving a golden light into their body (or what's left of it). The target is restored to life with half of its maximum hit points and original form. Much like resurrection, coming back to life is an ordeal. The target has -4 to attack rolls, skill checks, and ability checks and due to the forcible nature of the Utterance. They have disadvantage on these checks until their essence stops fluctuating. Each long rest reduces the -4 penalty by 1 until it is gone. If the soul of the target is unwilling to return to life they may make a CHA save to negate this effect.
You may speak this Utterence in reverse to rip the very essence of life out of a target whose personal Truename you know, pulling a golden light from their body and dealing necrotic damage equal to half of their remaining hit points. This damage is reduces their maximum hit points by the same amount until they take a long rest or are healed by a spell such as Greater Restoration.
This Utterance does not affect Undead.