The Predator film provided a variety of hardships for the actors, such as leeches, snakes, stifling humidity, heat and rough terrain. All of the night scenes were filmed during freezing-cold temperatures, which was especially hard on Arnold Schwarzenegger during the latter half of the film when the mud he had to wear (actually pottery clay) became cold and wet. He was warned it would take his body temperature down a few degrees and he shivered non-stop, even when they tried to heat him with lamps (it just made the clay dry out).