Staff of Artakha

The Staff of Artakha was an extremely powerful artifact the Toa Nuva needed to recover in preparation for Mata Nui's awakening. It was created by Artakha years ago, and had once been kept in the Onu-Metru Archives, but was eventually stolen in a raid by the Dark Hunters centuries ago.

The Toa Nuva went to Odina to recover the Staff, only to find it was not there. They next traveled to Xia to find it, believing "The Shadowed One" had it. Once there, Onua encountered Makuta Icarax, who had stolen the staff.

Teridax tried to recreate the Nui Stone with the staff (given to him by Icarax), but an interruption by Brutaka ceased this action. Brutaka passed the staff off to Botar, who brought it to Daxia. There, Helryx was able to use the Staff's power to repair all the damage to the Matoran Universe that the Great Cataclysm had done.

Powers
The Staff of Artakha possesses immense power. While in Daxia, Trinuma placed it in a pedestal, allowing it to repair the entire Matoran Universe; everything as a result of the Great Cataclysm was healed. This great feat was described as only a fraction of the staff's power. Despite this great power, the Staff still wasn't able to repair Karda Nui, because it was too heavily shielded.

Other than that, the Staff's power was being able to "heal" something, no matter how damaged it was.

Trivia

 * Even though the Staff was named after Artakha, this was not his weapon or tool, though he did create it.