Devilish Hunt

You conjure three barbed harpoons of intricately twisted silver. They float in the air above your head for the spell's duration and fade when it ends. When you cast the spell, and as an action on your subsequent turns, you can make a ranged spell attack to hurl a harpoon at a target within 90 feet of you. If you miss, the harpoon fades. If you hit, the target takes [roll]2d6[/roll] piercing damage and must make a Dexterity saving throw. If they fail, the harpoon lodges in their flesh. 

While a creature has been skewered by a harpoon, its speed is halved, and you can use a bonus action to cause an invisible chain to pull taut, hauling the creature 10 feet towards you for each harpoon lodged in it. The target can use an action to pull any number of harpoons out, taking [roll]3d6[/roll] necrotic damage for each harpoon removed and causing the harpoon to fade. Once all three harpoons have faded, the spell ends.