The Cloven Crystals are three magical items that resemble an amber cat's eye. The Crystals are critical to releasing Uk'otoa, acting as keys to its confinement. It rewards those who use Crystals to free it with control over water.
The Cloven Crystal has an amber-yellowish color. It has striations that refract light around it. At one end, there is a pointed oval line carved in about three inches across. With all three crystals deposited, Uk'otoa can be released to rule the Lucidian Ocean once again, just as it had done in ages past.
- Fjord's body/Sword of Fathoms
- Temple of Uk'otoa on Urukaxl (placed by Avantika)
- Underwater temple in Gravid Archipelago (placed by Fjord)
According to Avantika, Vandren already had a Cloven Crystal when she met him. Avantika and Vandren discovered another Cloven Crystal was being auctioned off in Port Damali. They stalked the collector who bought it to an unknown island and killed him. Avantika absorbed the crystal, causing Uk'otoa's eye to appear in her palm.
When Vandren abandoned the quest to release Uk'otoa, he took one Cloven Crystal with him. If Fjord's vision of Vandren absorbing the crystal was accurate, it means Vandren found a way to get the crystal out of his body. He kept it in a hidden compartment in the captain's quarters of the Tide's Breath. Avantika failed to find him or his crystal. She hired the Jagentoth family from Shadycreek Run to find a crystal and deliver it to Nicodranas.
"Lost Treasures" (2x22)
In the subterranean tunnels of the Labenda Swamp, the Mighty Nein found a Cloven Crystal resting in a pool of water. Fjord went to touch it and immediately entered a dreamlike trance, during which he saw a vision of his mentor, Vandren, standing over a body, thrusting the Crystal into his chest, and summoning the same falchion that Fjord wielded. Fjord also thrust the Cloven Crystal into his chest. After this incident, the falchion appeared to have a Cloven Crystal resting within it.
"The Journey Home" (2x30)
After killing Lorenzo and the Iron Shepherds, the Mighty Nein searched the house for evidence against the Jagentoth family, who employs the Iron Shepherds. When they turned Lorenzo's Bag of Holding inside out, they found a letter from Avantika.
"Dangerous Liaisons" (2x37)
"Dubious Pursuits" (2x40)
"The Diver's Grave" (2x44)
After failing to find the third Cloven Crystal upon the wreckage of the Tide's Breath whilst exploring the Diver's Grave, Fjord later discovered and absorbed the Cloven Crystal within the lair of Dashilla. His falchion now had two eyes, one in the hilt and one in the pommel.
"The Second Seal" (2x47)
After the Mighty Nein defeat the Deep scion and Chuul guarding the ruined temple located underwater at the Gravid Archipelago, Fjord deposits one of his Cloven Crystals at the location and is rewarded with the power to control water. Uk'otoa also gifts Fjord a vision of the third and final temple's location. 
- According to Avantika, Vandren already had a Cloven Crystal when she met him. This seems to confirm the accuracy of Fjord's vision of Vandren absorbing a Cloven Crystal after killing its previous owner.
- ↑ See "Lost Treasures" (2x22) at 3:01:46.
- ↑ See "Lost Treasures" (2x22) from 3:11:05 through 3:14:15. Fjord has a vision of Vandren absorbing a Cloven Crystal and simultaneously absorbs the Cloven Crystal found in the Gentleman's safe house
- ↑ See "Dubious Pursuits" (2x40) at 43:39.
- ↑ See "The Second Seal" (2x47).
- ↑ See "Dubious Pursuits" (2x40) from 3:01:29 through 3:02:44.
- ↑ See "A Hole In the Plan" (2x42) at 3:25:19.
- ↑ See "The Diver's Grave" (2x44) at 37:01. Jester finds a box that used to hold a Cloven Crystal
- ↑ See "The Journey Home" (2x30) at 50:58. The Mighty Nein find Avantika's instructions for delivering the crystal in a house owned by the Jagentoth family
- ↑ See "The Journey Home" (2x30) at 51:10.
- ↑ See "Dangerous Liaisons" (2x37).
- ↑ See "The Diver's Grave" (2x44) from 3:53:48 through 3:54:54.