Death Touch (5e Spell)
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You touch a creature and attempt to end its life instantly. If the target of your spell has more than 10 hit points this spell fails. The target of your spell must make a Constitution saving throw. On a failed save the creature takes 10 necrotic damage.
On a successful save nothing happens.
At Higher Levels. When you cast this spell using a spell slot of 2nd level or higher increase the hit point requirement by 10, and the damage taken by 1d10 for each slot level above 1st.
For example, if the spell is cast as a 2nd-level spell, the spell fails if the target has more than 20 hit points, and will do 1d10 + 10 necrotic damage on a failed save.