Makuta (2015)

The Shadowed One was one of the legendary Gods on Okoto and the brother of Takua. He originally wore the Mask of Ultimate Power and forged the infamous Mask of Shadow. He eventually became a renegade force on Okoto, seemingly responsible for most of the island's plagues.

History
The Shadowed One was once the legendary Protector of the okotans on Okoto, but was often overshadowed by his brother, whose masks were more favored by the island's denizens. The Shadowed One would attempt to prove himself as the superior of the two by giving Masks of Shadow to the islanders. This plan backfired, however, causing The Shadowed One's jealousy to reach the breaking point. In violation of a sacred law that no mask could contain the power of more than one element, The Shadowed One forged a heretical mask that contained the power of all six control it had took control of him, dubbed the Mask of Controls power. The Shadowed One attempted to demonstrate his new mask at the Capital City, but upon donning the mask its power of control proved to be too much for him to controlled by himself. Takua then knocked the mask off of his face, destroying it and seemingly destroying the city, while both of the crafters were put into a endless sleep. The Shadowed One and the city were both sent to the Shadow Realm as a result of the mask's explosion.

Despite having been purged into a deep slumber, The Shadowed One's spirit had remained active since then, and had influenced the Skull Creatures to do his bidding and search the island for the Masks of Power. This resulted in one Skull Creature, Kulta the Skull Grinder, obtaining the Mask of Creation and planning to melt it down at Ekimu's Forge.

After the Skull Creatures were defeated, Makuta bode his time within his prison, now using Umarak to obtain his former mask, the Mask of Control. The Shadowed One then used the mask to force Umarak to put it on, allowing him to take full control over the mask hunter's body and transforming him into a monster. . He then used his new body to locate fragments of the Mask of Control, scattered across the island when it was destroyed, in order to free him from the Shadow Realm. When The Shadowed One was about to be freed, the Toa stopped him by combining their elemental powers, resulting in The Shadowed One be forever remaining trapped in the Shadow Realm and the Toa returned to the stars, where they originally came from.

Powers and Tools
As a God, The Shadowed One was able to create masks of incredible power. He wielded a large hammer, which he used to forge his creations.

The Shadowed One's original mask was the Mask of Ultimate Power which has the capability of mind control and unspeakable powers. He later crafted the Mask of Control, which could control all six elements and the minds of other minds of other beings, but the mask was lost when Takua confronted him and knocked it from his face.

Trivia

 * Concept art for the 2013 online animations reveals that at one point the BIONICLE team considered making The Shadowed One's armor gold instead of silver, and he would have had his own Okotan Mask in addition to the Mask of Ultimate Power as well as the Mask of Control.