BIONICLE Legends 4: Legacy of Evil

Legacy of Evil is the fourth Bionicle Legends book and came out 2006

Story
These events take place roughly 7000 years before the events of Bionicle Legends

Vezok and Hakann raid a Toa Fortress for a treasure rumored to be inside (or, more accurately, Vezok raids it while Hakann is left to fight off the guards). Vezok finds that the treasure is a tablet called the Makoki stone, and that the tablet is covered with hidden writing concerning the Brotherhood of Makuta. Vezok takes the stone, but the two thieves are caught and forcibly recruited into the Dark Hunters (joining the other four future Piraka), who take the Makoki stone for themselves.

These events take place roughly 5000 years before the events of Bionicle Legends

Zaktan leads the others (minus Avak) in a plot to overthrow "The Shadowed One", but they are caught. When The Shadowed One tries to execute Zaktan with his disintegration vision, Zaktan surprises everyone (including himself) by surviving as a mass of Protodites.

These events take place roughly 4000 years before the events of Bionicle Legends

Reidak, Vezok, and Avak free the Kanohi Dragon from its icy prison, letting it loose on Metru Nui. They then go to Turaga Dume offering the Hunter's "protection". Dume refuses, but just as Vezok tries to kill him, Toa Lhikan, Toa Nidhiki, and the rest of their team intervene. The Hunters leave to try again later, while the Toa fight off the Kanohi Dragon. The Toa finally defeat the dragon after a month, and have it deported to Roodaka's homeland.

These events take place roughly 3000 years before the events of Bionicle Legends

In the war between the Toa and the Dark Hunters, Hakann watches Nidhiki betray the Toa and he catches Lhikan overhearing the betrayal. In an attempt to ensure his own freedom, Hakann offers a deal: Lhikan could have the Makoki stone back if he allows the defeated Hunters to go free. Knowing that his fellow Toa gave their lives to protect the stone, he agrees - with the condition that the Hunters take Nidhiki with them. Six months later, "The Shadowed One" has the stone stolen back, split into six, and auctioned off to the Brotherhood of Makuta, he also has Roodaka mutate Nidhiki, dooming him to a lifetime with the Hunters.

These events take place roughly 250 years before the events of Bionicle Legends

Zaktan, Thok, and Reidak are protecting a base in the war against the Brotherhood. After Roodaka tips them off that the base used to belong to the Brotherhood, Zaktan investigates and discovers an entire record of the Great Cataclysm. After getting over the shock of the depth and evil of the Brotherhood of Makuta's plans, Zaktan vows to make himself become part of them.

Characters

 * Piraka
 * Vezon
 * Lhikan's Team
 * Roodaka
 * Kanohi Dragon
 * "The Shadowed One"
 * Toa of Plantlife