A 6-inch-long maggot forms inside a creature of your choice within range and begins to devour the target from within. Make a melee spell attack against your target while in range. On a hit, the target takes necrotic damage from the maggot equal to 1d8 + your spellcasting ability modifier. As a bonus action on each of your subsequent turns, you can repeat the attack against your target.   As an action on its turn, your target can make a melee weapon attack against the maggot with a weapon that deals piercing or slashing damage. The maggot has AC equal to your spell save DC and 8 hit points per spell slot level used to create it. If your target hits the maggot, half of the damage is dealt to the maggot, and the other half is dealt to the target itself. If the maggot is killed, the spell ends.