Mantax

Mantax resented Pridak for leading him into disaster - first by being banished to The Pit, and again when Mahri Nui crushed the Barraki fortress. However, he was wary of Carapar, as he has lost when the two have fought in the past.

It has been confirmed that Mantax was in fact looking for a contract stating that one Barraki betrayed the League of Six Kingdoms to the Brotherhood of Makuta.

BIONICLE.com Disscreption
"Dweller in darkness ... the most secretive and mysterious of the Barraki. Spends most of his time buried in the sea floor, with only his eyes and head spikes visible, waiting for prey to swim by. When he's not there, he is down in the flooded remains of the original Pit, for reasons unknown. Traditionally keeps silent and in the shadows, preferring not to share information with the other Barraki unless he has to (knowledge is power, after all). Commands an army of Rays."

Powers and Tools
Mantax's natural weapons included a pincer, head spikes with paralyzing venom, a tentacle on the back of his head that conducts lightning, and armored shoulder plates, he also had a Squid Launcher.

It is possible he can detect electrical fields as Pridak can.

Army
Mantax's army included a large number of organic undersea rays. They were mentioned near the end of BIONICLE Legends #7: Prisoners of the Pit, and will most likely appear in BIONICLE Legends #8: Downfall.

Trivia

 * Like the other Barraki, Mantax was based on a real-life sea creature. Mantax was most likely based off a Manta Ray.
 * Mantax's undersea rays were last seen destroying everything in their path - with Toa Mahri Hahli in the lead.