Mari is a toa of water who is best friends with Helryx. When Helryx was visiting Drogo Nui,Helyx found a toa stone and gave it to Mari. She was examining it,when a rahi beast draged her underwater. She found an old suva underwater and became a toa.She was trying to destroy the Dark Hunters,but a Makuta who betrayed the Brotherhood of Makuta infected her mask. She was uninfected by Verendus,who at the time was a matoran.