Choose a humanoid that you can see within range. The target must succeed on a Constitution saving throw or be controlled by you for the duration.

While a creature is controlled by you, you may use a bonus action on your turn to direct the movement of the creature, up to its movement speed, and direct it to make one melee attack against a target that you choose, if there is one in range. 

At the start of each of its turns, the target can make another Constitution saving throw. On a success, the spell ends on the target and you take 3d10 necrotic damage. On a failed save, the creature takes 3d10 necrotic damage and remains in your control for the duration.

If the target drops to 0 hit points due to this damage, then the creature remains in your control for the duration and may no longer make Constitution saving throws at the start of its turn.