You create shackles of force that attach to the target's limbs. You designate an object or location within 30 feet of the target for the shackles to anchor themselves to; this must be the ground, a wall, or a sturdy structure for the anchoring to occur. The target is entangled, and cannot move more than 30 feet from the anchor point of the spell. The shackle itself cannot be attacked (though it can be dispelled), but if the object or area it is attached to is broken, the target is free to move away (though it is still entangled).