Spear of Fusion

The Spear of Fusion was an artifact with the ability to fuse and defuse two beings.

History
A tool like the Spear of Fusion was used by a Dark Hunter to make "Prototype" out of a Toa of Fire and a Toa of Earth who were just about to fuse into a Kaita-like being.

The Piraka found the Spear in Mangaia while searching for artifacts to steal from Makuta's base. Hakann accidentally fired it at Vezok, splitting him into two beings - himself and Vezon. When a Mana-Ko attacked them, Vezon escaped the Piraka and ran away with the spear.

In the Chamber of Life, once the Piraka had arrived there, Vezon used the spear to fuse Vezok and Reidak into the Piraka Fusion. He later unfused them once the combination had defeated the remaining four Piraka. After the Toa Inika had defeated Vezon and Kardas, Vezok wanted somebody to fuse him back to Vezon. But Zaktan knew that the Piraka needed to follow the Toa Inika immediately, and ordered Reidak to snap it in half.

Vezon then presumably took it with him after the Inika's Zamor sphere wore off. It has been confirmed to still work despite being broken.