 The production staff also spread sand onto the floor of the cave sets in order to make it look different from other episodes in which the sets had been used.Burton advised Farrell on the aggressiveness Dax should show in her interactions with Kor and Worf in the episode, a type of performance which both Burton and Farrell later nicknamed "Action Barbie".John Colicos had appeared as Kor once before on "DS9", in the second-season episode "".