Autumn's Decay

You advance the natural cycle of life in a target creature you touch, causing it to feel the burden of age. The target must make a Constitution saving throw, rolling with disadvantage if it is a plant creature. On a failed save, the creature takes 6d6 necrotic damage, it has disadvantage on Strength and Dexterity checks for the duration of the spell, and its speed is halved for the duration of the spell. On a successful save, the creature takes half as much damage, doesn’t have disadvantage on Strength and Dexterity checks, and doesn’t have its speed reduced.