The Nokk

The Nokk is an important character in the upcoming 2019 Disney movie Frozen II. It is a water spirit that guards the ocean and uses it to test people to see if they are worthy.

Appearance
The Nokk mostly takes the form of a horse that is made out of water.

Jack Frost
Since the Nokk is a spirit, like Jack is, there is a chance that they'll come across each other.

Moana Waialiki
Because the Nokk comes from the ocean and is a water spirit, there is a chance that Moana's friendship with the Ocean would allow her to meet one.