The Ultra-Gorgon was built in a disused church. Members of Jim Henson's Creature Shop couldn't begin construction until they got into the church, which was about five weeks before shooting began. Since the character was intended to look like an unfinished special-effects monster, the team decided to build until they ran out of time, starting from the feet upward. Three nights before production began, the Ultra-Gorgon's wings arrived at the build site.