The Lion King

The Lion King is a popular movie about a young lion in Africa who is a prince and his journey to become king.

Thing was a fan of the movie. When he learned that Black Panther was actually the chief of the African nation of Wakanda, he noted that he had clobbered "the lion king."

Background
The film was made by The Walt Disney Company, who would later purchase Marvel Entertainment. It features the voices of Jim Cummings, Frank Welker, and Phil Proctor.

In, there is a visual reference to the film with holding his son  before the kingdom just like the opening scene. That film also featured the father dying and the son eventually taking up his family mantle.