Skulls and Shackles
Crafted from the jagged tusk of a narwhal
This +1 returning harpoon (Pirates of the Inner Sea 18) is made from the jagged, scrimshaw-carved tusk of a narwhal attached to a 50-foot length of woven sinew. Unlike most thrown weapons, a vindictive harpoon functions as well underwater as on land, and its wielder takes no penalties on attack rolls underwater.
Requirements: Craft Magic Arms and Armor, freedom of movement, telekinesis; Cost 5,305 gp