Arachnid Arcanarm

After attuning to this item this contraption binds itself to your back, appearing as a segmented plate running all the way down. As a bonus action you can speak the item’s command word to activate or deactivate it. Upon activation, the appendage slowly detaches from your back and curls up into a tail. At the tip of the tail lies an ethereal harpoon resembling the stinger of a scorpion.

While activated, the prosthetic tail provides these benefits:

• The prosthetic is a fully capable part of your body however it is not dexterous enough to use weapons, magic weapons, and other specialized equipment.
• You can take an action to remove the prosthetic, and it removes itself if your attunement to it ends. It can't be removed against your will.

This prosthetic has 6 charges, and recharges 1d6 charges at dawn. When you take the Attack action on your turn, you can replace one attack with one of the following:

Grappling Hook (1 Charge): You propel your ethereal stinger towards a surface within 60 ft, anchoring the point in place. While anchored, you cannot be moved more than 60 feet away from the point of attachment. Once per turn while anchored, you can propel yourself and one willing creature of your size or smaller within 5 ft to the point of attachment. You may use an object interaction to remove the anchor from the surface it is latched onto. You cannot use other abilities from this appendage while this effect is active.

Force Spear (1 Charge): You expel your ethereal stinger in a straight line out to 60 ft, piercing through any enemies that lie in its trajectory. Each creature caught in the line must make a DC17 Dexterity saving throw, taking 1d8 force damage on a failure.

Ethereal Tether (3 Charges): You shoot an ethereal harpoon out towards a single creature within 60 ft, attempting to latch onto the creature's soul. The creature must attempt a DC17 Charisma saving throw. On a failure, the target suffers 3d8 force damage and becomes grappled. On a success, the creature takes half damage and is not grappled. While grappled in this way, a creature cannot use any movement or ability that would move it farther away from you, including teleportation or extra-planar travel. The creature can repeat this saving throw on the end of each of its turns to end the grapple. Maintaining this effect requires your concentration. You cannot use other abilities from this appendage while this effect is active.

Notes: Warforged