|BIONICLE Adventures 2: Trial by Fire|
|Number in series||2|
|Previous book||BIONICLE Adventures 1: Mystery of Metru Nui|
|Current book||BIONICLE Adventures 2: Trial by Fire|
|Next book||BIONICLE Adventures 3: The Darkness Below|
In Ta-Metru, Nidhiki nearly sends Onewa and Vakama to their death. They are caught in a chute headed right for the flames of the Protodermis Reclamation Furnace. Vakama absorbs the flames of the furnace and releases the heat in a beam which blasts through the roof of the building.
Whenua and Nuju enter the wrong room while searching the Archives for the Onu-Metru Great Disk, and find themselves in the grip of a Giant Mutant Ussal Crab. They escape by chasing it off with a high-frequency sound generated by Whenua's drills.
Nokama and Matau, searching for the Ga-Metru Great Disk, are nearly drowned when water is released into a the previously dry canal they were walking through. Nokama rescues Matau. Nokama gets the Great Disk from inside the mouth of a massive fish in the water under the Great Temple, but is chased by the fish and nearly eaten.
Onewa, Vakama, and the Matoran Ahkmou and Nuhrii search for the Ta-Metru Great Disk in the Fire Pits. Vakama and Nuhrii descend into one pit while the fires it houses had died down, and retrieve the Great Disk. But Morbuzakh vines grab them on their way out. Nuhrii uses a Kanoka with the power of Reconstitute at Random on the vines; the shock of transforming makes the vines let go. They escape, chased by a monstrous reconstituted vine, just in time before the pit's fires erupt again.
Nuju almost releases a Two-headed Tarakava from its tank in the Archives by accident. Shortly after, he and Whenua find themselves trapped in a room with nothing in it... because the "room" itself is a shape-shifting Rahi. They escape after Nuju summons a blizzard, which the "room Rahi" dislikes. Whenua finally finds the Great Disk in a room stuffed with all sorts of artifacts.
Matau enters a Force Sphere to retrieve the Le-Metru Great Disk, only narrowly escaping with the Disk before it implodes.
Searching for the Po-Metru Great Disk, Vakama and Onewa encounter a rogue Tunneler. They defeat it by making it turn itself into glass, so it's too fragile to move without shattering. Onewa gets the Great Disk from the top of an unstable statue, narrowly avoiding being crushed by it. With all of the Great disks found, the Toa meet up.
Vhisola reveals how to defeat the Morbuzakh - the Toa Metru must find the King Root. Nokama realizes the King Root must be in the Great Furnace. On the way to the King Root, the Toa Metru encounter and escape from hundreds of Morbuzakh seeds. Ahkmou tries to run. Onewa realizes he was definitely the traitor, and confronts him about it. In the hallway leading to the Great Furnace, Nuju uses up most of his elemental power trying to defeat several vines blocking the way. Then the Toa and Matoran are nearly defeated when hundreds of thorns are shot at them. Nuhrii, Tehutti, Orkahm, Vhisola, Ahkmou, and Ehrye form a Matoran Nui, and this merged being helps the Toa escape into the main chamber. The Matoran, then separate, flee the building.
The Toa enter the Great Furnace. They see the King Root, as tall as a skyscraper, filling the massive room. The King Root speaks telepathically to the Toa, revealing that it was commanded to drive the Matoran to the center of the city. It tries to steal Whenua's Great Disk, but fails. During the battle, the Toa Metru each use up almost all of their Elemental Power (it would later take quite some time to recharge due to their inexperience as Toa), and trick the Morbuzakh to draw them in closer to it. They then launch the Great Disks, which form an energy bubble around the King Root, cutting it off from its vines, and killing it. The Toa Metru retrieve the Great Disks, and flee as the building collapses. The vines in the city disintegrate. The Toa have been victorious... but Nokama wonders who could have commanded the Morbuzakh, and whether that person would strike again.
- Matoran Nui