A powerful winged-serpent alien who once visited Earth and was worshipped by the Maya and Aztecs, and who demands worship from the Enterprise crew.
Kukulkan is a long-lived alien who resembles a winged, feathered serpent. In How Sharper Than a Serpent's Tooth, he immobilizes the Enterprise and transports Kirk, McCoy, Scott and Ensign Walking Bear to his ship, claiming to be the god of the ancient Maya and Aztecs and wanting humanity to worship him again.
He visited many Earth cultures, teaching each part of his knowledge and leaving instructions for a signal to recall him, which none fully carried out. Kirk solves the riddle of his recreated city and argues that humanity has outgrown the need for him. Kukulkan finally releases them.