The stop-motion techniques of Willis O'Brien went on to bring dinosaurs to life in the 1933 film "King Kong", which merged the tropes of dinosaur combat and dinosaurs in a lost world. His protégé Ray Harryhausen would continue to refine this method, but most later dinosaurs movies until the advent of CGI would eschew such expensive effects for cheaper methods, such as humans in dinosaur suits and modern reptiles with dinosaur decorations, enlarged by cinematography. Dinosaur depictions diversified in the 1930s, spreading to newspaper comic strips in "Alley Oop" and to advertising for Sinclair Oil.