Anchor of Striking

This small rusty iron anchor feels sturdy in spite of its appearance. You gain a +1 bonus to attack and damage rolls made with this magic war pick. When you roll a 20 on an attack roll made with this weapon, the target is wrapped in ethereal golden chains that extend from the bottom of the anchor. As an action, the chained target can make a DC 15 Strength or Dexterity check, freeing itself from the chains on a success. Alternatively, you can use a bonus action to command the chains to disappear, freeing the target. The chains are constructed of magical force and can't be damaged, though they can be destroyed with a disintegrate spell. While the target is wrapped in these chains, you and the target can't move further than 50 feet from each other.