The next time you hit a creature with a ranged weapon attack before the spell ends, this spell creates an onyx serpent that strikes the target from your ranged weapon or ammunition. In addition to the normal effect of the attack, the target suffers 1d12 poison damage. The target loses immunity to poison damage and the poisoned condition and gains resistance to poison damage instead. If the target was not immune to poison damage but was resistant then the target loses that resistance instead. This effect lasts for 1 minute or until the caster loses concentration on the spell. The target can end this effect early by succeeding a constitution saving throw at the end of their turn. The target can repeat this saving throw at the end of each of their turns.