Complex sentence: Meddings, who was previously known for his work on "Superman" (1978) and its 1980 sequel, led the special effects department of "Krull" and created miniatures for the setting of the film's titular planet.
Split into simpler sentences: Meddings, who was previously known for his work on "Superman" (1978) and its 1980 sequel, led the special effects department of "Krull". Meddings created miniatures for the setting of the film's titular planet.