This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Kushtaka (Tlingit)
Kooshdaa kaa or Kushtaka ("land otter man") are mythical shape-shifting creatures found in the folklore of the Tlingit peoples of the Pacific Northwest Coast of North America. They are similar to the Watsa of the Ts'msyen people, Nat'ina of the Dena'ina Native Americans of South Central Alaska, and the Urayuli of the Yup'ik in Western Alaska.
Physically, Kushtaka are shape-shifters capable of assuming human form, the form of an otter and potentially other forms. In some accounts, a Kushtaka is able to assume the form of any species of otter; in others, only one. Accounts of their behaviour seem to conflict with one another. In some stories, Kushtaka are cruel creatures who take delight in tricking poor Tlingit sailors to their deaths and in others, they are friendly and helpful.