Everlasting Poison (5e Spell)
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|V, S, M (a wyvern's tooth, consumed by the spell)
You jab the tooth into your body, as it disintegrates into your blood stream, as you then make a magical jab at your target. Make a melee spell attack against the target. On a hit, they take 3d6 poison damage, and the poison is transferred to them. If you miss, or they take no damage, you instead take the damage and become the new target of the spell.
At the start of the target's turn, they must make a Constitution saving throw. Regardless of whether they succeed or fail, they then take 3d6 poison damage. Until the target succeeds three different times, the spell does not end. The spell can be forced to end by a healing spell of one level higher than this spell was cast at, the wish spell, or similar effects.
At Higher Levels. When cast at 9th level, a target has disadvantage on the saving throw.