Three Klingons in particular made quite an impression on Star Trek: The Original Series and helped to establish the temperaments of many of the Klingons that followed.Kor (John Colicos), Koloth ...

If John Colicos had turned down the chance to return as Kor from Star Trek: The Original Series, then Peter Allan Fields would have to have created a new Klingon to join Kang and Koloth's quest.