The Predator by John McTiernan was first designed by a special effects company the studio picked to save money on. Stan Winston later created the Predator for $1.5 million; this other studio charged half that amount. Because of that, their Predator looked like someone in a lizard suit with the head of a duck, according to Arnold Schwarzenegger.
When Winston was brought in to redesign the Predator, the final fight scene had to be reshot. The new Predator was 8-1/2 feet tall, but the recast Kevin Peter Hall was 7'2'. The costume was heavy and off-balance and Hall couldn't see with the mask on; because of that, during the fight scene with Dutch, he actually did hit Schwarzenegger once.
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).
The Yautja, known colloquially as the Predators or Hunters, are an extraterrestrial species characterized by their hunting of other dangerous species for sport and honor, including humans. They were also referred to once as Xenopredators. The Yautja are a sentient, humanoid race that breathe an atmosphere similar to that of Earth's, but possess a level of technological advancement far in excess of anything available to humans.