Mo'at is the Tsahìk, or spiritual leader of the Omaticaya clan. She is seen as a psychic or a 'bridge' to the Na'vi beliefs - more specifically, Eywa. Mo'at was mated with the former clan leader, Eytukan, and had two children: Neytiri and Sylwanin.
When Neytiri brought Jake Sully to the Omaticaya, Mo'at examined him and asked for his name and purpose of his presence. Jake presented himself as a warrior who wished to learn the ways of the Na'vi. Mo'at told Neytiri to teach Jake the Na'vi culture, and her daughter reluctantly accepted the responsibility.
Later, however, Mo'at began to regret her decision as Jake and Neytiri began to fall in love. When Tsu'tey, who was intended to become Neytiri's mate, realized that Jake and Neytiri had mated, Mo'at asked Neytiri if it was true and she confirmed that it was. Mo'at was not happy about this and was even less happy when Jake revealed that he has been ordered to spy on the Na'vi. Despite learning that Jake had infiltrated the Omaticaya with the original intent of deception, she freed both Jake and Grace Augustine during the RDA's attack on Hometree after the Na'vi had fled into the woods, desperately requesting Jake's help after doing so. However, the Hometree was destroyed and Mo'at was, like the rest of the clan, distraught.
Together with the survivors, Mo'at journeyed to the Tree of Souls where the clan prayed to Eywa for aid. When Jake returned to the clan as Toruk Makto and told her that Grace was dying, Mo'at tried to save her by performing a consciousness transfer ritual, supported by prayers from the clan. However, Grace died from her injuries.
During the assault on the Tree of Souls, Mo'at was watching the battle from under the tree. After the Na'vi triumphed over the Sky People and banished them from Pandora, Mo'at attempted to transfer Jake's consciousness permanently into his avatar body. This time, the ritual succeeded.
As the Tsahìk of the Omaticaya clan, Mo'at possessed a strong connection to Eywa as well as possessing great wisdom. She tried to keep the peace within the clan. Mo'at initially disapproved of Jake and Neytiri's relationship; though she had been the one who ordered Neytiri to teach Jake the ways of the Na'vi, she did not intend for them to fall in love. Nevertheless, she seemed to harbour much respect for Jake, especially after he became the sixth Toruk Makto in Na'vi history.
Mo'at loved her daughter and her mate a great deal and cared deeply for her people. She cared so much about her clan that she was even willing to put aside betrayal and deception in order to keep her people safe, as proven when she freed Jake and Grace Augustine from their bindings during the destruction of Hometree and pleaded with Jake to save her people.
Mo'at possessed great knowledge about consciousness transfers and had the ability to lead the ritual that transfers a human's consciousness permanently into his or her respective avatar.
Eytukan was Mo'at's mate and with him, she had two daughters, Neytiri and Sylwanin. Mo'at had a significant influence on her mate's decisions. When Eytukan was killed in the assault on Hometree, she and Neytiri both mourned him. Eytukan was the second member of Mo'at's family who was killed by Sky People.
Mo'at loves her daughter, Neytiri, a great deal, but expects her to treat her with respect. When she ordered Neytiri to teach Jake Sully in the ways of the Na'vi, she stopped Neytiri from arguing with her. However, Neytiri falls in love with Jake and disobeys Mo'at and Eytukan by mating with him. At first, Mo'at was disappointed in her daughter but later accepted her decision after Jake atoned for his initial betrayal by becoming the sixth Toruk Makto and aligning himself with the clan.
Sylwanin was Mo'at's eldest daughter. It is unknown exactly how close they were but after Sylwanin's death at the hands of Sky People, both Mo'at and Eytukan forbade all Sky People from entering their territory.
Mo'at first met Jake when Neytiri and Tsu'tey brought him to Hometree and ordered Neytiri to teach him their ways. Mo'at soon grew to respect Jake but was disapproving of his relationship with Neytiri. Despite admitting to being ordered by the RDA to spy on the clan, Mo'at freed both him and Grace from their restraints during the RDA's assault on Hometree and begged for Jake's help. Mo'at was amazed when Jake became Toruk Makto. She later performed a ritual to transfer Jake's consciousness into his avatar body and the ritual succeeded.
"We have tried to teach other Sky People... It is hard to fill a cup which is already full."
- -Mo'at talking to Jake Sully on their first meeting.
"Learn well, Jakesully, then we will see if your insanity can be cured."
- -Mo'at to Jake upon his introduction to the Omaticaya clan.
"If you are one of us, help us!"
- -Mo'at pleading with Jake to help the clan when the RDA forces attacked Hometree.
Mo'at: "The Great Mother may choose to save all that she is, in this body." Jake: "Is that possible?" Mo'at: "She must pass through the eye of Eywa and return. But, Jakesully, she is very weak."
- -Mo'at warning Jake that Grace's transition may be problematic.
"Her wounds were too great. It was not enough time. She is with Eywa now."
- -Mo'at to Jake after Grace dies during the consciousness transfer process.