Kerato

Kerato was the Protector of Stone at the time of the Battle of the Mask Makers, serving alongside Uganu, Agarak, Mamuk, Owaki, and Etoku. A staunch ally of Ekimu, Kerato received a new Protector Mask from him at the Festival of Masks, after which the Protectors and Ekimu learned of Makuta's efforts to create a mask that combined multiple Elements. After seeing the Elemental Creatures, Ekimu and the Protectors traveled to the Temple of Time, where Ekimu donned the Mask of Time and learned of a coming cataclysm and the eventual arrival of the Toa on Okoto. With the exception of Agarak, all the Protectors then set out on a journey to obtain Elemental Crystals from the Creatures in order to power the Golden Masks that would later be worn by the Toa, with Kerato receiving a crystal from Ketar, Creature of Stone.

The Protectors later accompanied Ekimu to Capital City in an effort to stop Makuta from using his Mask of Ultimate Power, only to watch as Ekimu used the Hammer of Power against his brother. The resulting explosion sent Makuta and Capital City into the Shadow Realm while Ekimu was left in a coma, with the Mask of Creation, Mask of Control, the Golden Masks of the Toa, and the fragments of the Forbidden Mask being scattered across Okoto. Kerato and the other Protectors then carried Ekimu's body back to the City of the Mask Makers, and afterwards set about the task of finding the missing masks. The role of Protector of Stone would continue to be passed down to Kerato's descendants, with the most recent holder of the title being Nilkuu.

Trivia

 * Like all of the ancient Protectors except Agarak, Kerato's gender is unknown; it is also unknown whether Kerato was one of the Protectors who fought the Skull Raiders alongside Ekimu and Makuta.