BIONICLE Adventures 6: Maze of Shadows

Maze of Shadows is the sixth Bionicle Adventures book and came out 2004.

Story
The Toa Metru had just landed on the island that would soon be known as Mata Nui. Each of the Toa explore it and find a place to build their koro (villages). While deciding a spot for Ta-Koro, Vakama has a vision in which his Toa power disappears. Then he gathered six stones, and the Toa Metru invested some of their energy into it. Onewa had found a tunnel that he thought would lead to Metru Nui. They went through it, encountering a nest of sleeping Bohrok, an elite Vahki called a Kranua, mutant Rahi and the Rahi Nui. During the battle with the Rahi Nui, Nokama was poisoned and fatally wounded. While the Toa argued about whether to bring her to Metru Nui or back to the island above, vines come out and grabbed the Toa Metru. The vines belonged not to the Morbuzahk, but a prototype, named Karzahni. The Karzahni offered to heal Nokama if they got it some energized protodermis, which was the substance that was mutating the Rahi. The Toa Metru got some after defeating the energized protodermis entity.Then they gave to the Karzahni, but since its destiny wasn't to be transformed, it died.

Characters
Toa Vllains
 * Vakama
 * Nuju
 * Whenua
 * Nokama
 * Matau
 * Onewa
 * Energized protodermis entity
 * Rahi Nui
 * Karzahni