Uk'otoa

 is a leviathan imprisoned under the Lucidian Ocean and Fjord's patron. As an NPC, is played by Matthew Mercer.

Appearance
Legend says that Uk'otoa is a large serpent-like creature with three eyes in its head and many eyes along its body. On the altar above Captain Avantika's door aboard the Squall-Eater, it's represented by an ouroboros with nine eyes.

Background
Uk'otoa is a creation of Zehir, the Cloaked Serpent, left to rule the entirety of the Lucidian Ocean as his proxy after he was banished during the Calamity.

The Ki'Nau of the Swavain Islands were granted the blessings of Uk'otoa. Captain Avantika expressed that, with this blessing, "nothing and no one could stand before them." However, the surviving worshipers of the Cloaked Serpent grew jealous, sealing Uk'otoa beneath the depths of the Lucidian Ocean and defaced the temples built in their name.

Fjord's patron contacted him for the first time through a dream. He found himself underwater, facing an enormous, yellow eye. He tried to speak to it, but it responded only in single words: "Watching. Potential. Learn. Grow. Provoke. Consume. Reward. Patience." He woke with a start, coughing up seawater, and finds that his falchion is missing from its sheath. Fjord discovered he had bonded with the sword as his warlock pact weapon.

As Fjord fell asleep, he faded into a dream of himself standing in total darkness. In his hand was the Waste Hunter Blade. A large yellow eye appeared in front of him. A voice said "Consume". Fjord opened his mouth and pushed the sword into it. He felt pain but also a strong hunger and continued to push the sword further. After he had swallowed the sword, the voice said "Good". The eye closed. Fjord realized he was underwater and started trying to swim against the current. After a few seconds of struggling, he woke up suddenly. The Waste Hunter Blade was gone. Fjord wiped his mouth and found a little bit of blood. He summoned his pact weapon. Instead of the Waste Hunter Blade, his weapon took the form of his falchion again, but it had a more curved appearance similar to the Waste Hunter Blade.

Fjord hears his patron's voice in his head say "Learn" leading him to dive into a dark pool in the Merrow lair.

After the Mighty Nein defeat the merrow in the ruins, Fjord touches a yellow orb found in the chamber. Fjord was immediately transported into a vision. He saw himself in a different place wearing different clothes in a human body. Standing over the body of its previous owner, Fjord held the yellow orb in his hand. The right hand in the vision summoned the same falchion Fjord has. He heard a voice in his head say "Potential". He felt uncontrollably hungry then pushed the orb into his stomach. It went into him painlessly as a voice said "Consume". The hunger went away. Suddenly feeling exhausted, he fell to his knees. Fjord looked into a nearby pond, and saw Vandren's reflection instead of his own. The voice said "Reward". Fjord came back to his own body looking into the pool where the orb was found, but orb was gone. The next time Fjord summoned the falchion it had a yellow eye in the center of the hilt.

The Mighty Nein met Avantika and discovered she is also a follower of Fjord's patron. She told them its identity- Uk'otoa the great leviathan. That night, Fjord had a dream of being under the ocean.

As Fjord touched the Cloven Crystal to his chest, his vision went black. He saw the same dark ocean and three yellow eyes he had seen in dreams before. An endless row of teeth smiling at him appeared and the vision was gone.

Sleeping outside the city of Asarius, Uk'otoa revealed himself to Fjord, adding the words Wander, and Punish, before crushing him in the dream.

Avantika
Uk'otoa communicated with Avantika through dreams. It is implied she had less contact with Uk'otoa than Fjord, saying in "Dangerous Liaisons" that it had been a few years since her last dream. Avantika had a yellow eye similar to the eye on Fjord's falchion in the palm of her right hand. She claimed the eye appeared after she killed the previous owner of the Cloven Crystal.

Uk'otoa granted her the power to manipulate water after she brought a Cloven Crystal to its temple on Urukaxl.

Fjord
Uk'otoa communicates with Fjord mostly through dreams. Fjord never had these dreams or the ability to use magic before finding his falchion.. In his dreams, Fjord is often underwater and sees a giant yellow eye. Fjord's attempts to speak to the entity have resulted in single word responses or no response at all. So far he has heard the words: "Watching, Potential, Learn, Grow, Provoke, Consume, Reward, Patience, Good, Release, Wander, and Punish" in various dreams. Some of these dreams have physical side effects when Fjord wakes up. The dreams have sometimes included people from Fjord's past- Sabian, Vandren, and Avantika.

Fjord has only felt Uk'otoa's presence while awake when a Cloven Crystal was nearby.

Vandren
Vandren had a sword with an eye similar to Fjord's before the shipwreck caused by Sabian. At some point in the past, Vandren was working with Avantika to release Uk'otoa, but changed his mind.

Unknown Entities
In the Yuan-Ti temple on Urukaxl, the Mighty Nein saw three murals - depicting a giant purple bird with fire-like wings and three eyes of onyx, a gigantic sea serpent emerging from the water, with many small eyes of amber and three large eyes, and a worm-like creature with three eyes of ivory inside its mouth, plowing through the earth.

Abilities

 * Uk'otoa is able to communicate with his followers by gifting them dreams and visions.
 * As a entity of notable power Uk'otoa is able to gift his followers with the ability to control water, he is said to have done this in the past with the Ki'Nau, and more recently has done so to Avantika and Fjord as a reward for using their Cloven Crystals to unlock some of the binds holding him captive.

Notable Items

 * Cloven Crystals - Three orbs that are used as keys to release Uk'otoa. They are to be used in three temples scattered about. Two have currently been deposited in their respective temples located at Urukaxl and the Gravid Archipelago, the third and final one remains in Fjord's possession.

Quotations

 * "Watching. Potential. Learn. Grow. Provoke. Consume. Reward. Patience." - Fjord hears the voice of Uk'otoa in his head during a dream.
 * "Watching. Adapt. Reward. Release." Said to Fjord within a vision after he inserts the key into the second temple.
 * "Watching. Return. Reward. Wander. Punish. Said to Fjord in a dream after Fjord ignored Uk'otoa's third temple.

Trivia

 * The players have a habit of repeating Uk'otoa's name in hushed whispers when a character speaks it out loud.
 * The unlocking of Uk'otoa's temples is similar in nature to the Seven Seals in the Book of Revelation. According to the Christian Bible, when a seal is opened, a divine judgment or apocalyptic event occurs. The first four seals are commonly known as the "Four Horseman of the Apocalypse": Conquest, War, Famine, and Death.
 * Avantika could be interpreted as a metaphor for Conquest. As a zealot of Uk'otoa, she has preached the gospel truth of her patron to her crew, and she seeks to advance Uk'otoa's goal of release. Likewise, Avantika's desire to rule the seas and the pirates of the Revelry can be viewed as the crown given to Conquest.
 * Time will tell if Fjord will follow in the footsteps of War. Like War, Fjord had divine power given to him. Fjord's falchion can be interpreted as the "great sword" given to War. War is said to unleash global war, as the kingdoms of mankind slaughter each other. Given the war ongoing between the Dwendalian Empire and Xhorhas, this hints that the war might have dire consequences for civilizations across Exandria. However, it is unknown what role (if any) Fjord might play in this war or any war to come, let alone if Fjord would seek world supremacy with or without Uk'otoa.
 * Uk'otoa's name bears close resemblance to the race of degenerate fishmen, the kuo-toa. Despite the similarity it is currently unknown, whether Uk'otoa, or its creator, the Cloaked Serpent has any connection to these creatures.
 * Matt confirmed in that the reward for putting a Cloven Crystal in place to unseal Uk'otoa is a free Eldritch Invocation. This invocation, nicknamed "Dank Water Powers" gives the power to cast Control Water once per day without expending a spell slot.
 * Matt seemingly confirmed in that the three entities pictured in the yuan-ti temple, including Uk'otoa, are all creations of The Cloaked Serpent. He said some creations of the gods became "pseudo-gods" after being left behind by their creators.