Toa Nuva vs Makuta.

After a long and arduous trek through the land of Xia, Onua Nuva has arrived to claim the Staff of Artakha. But when he arrives, the warrior that stands before him claims to be Makuta… but not the one he had once known. Yet as the bearer of the Mask of Shadows and wielding the same multitude of powers Teridax himself held, the enemy Onua now faces is formidable and merciless. Only time will tell if the former will live to tell of him.

The Annals of Icarax resume here.