The Horned Mutant from Lost in Space was not a native creature to Preplanis. It landed on the planet within a meteor and stalked the Jupiter 2 while John, Don, Will, and the Robot had gone out to prepare a relay. It finally struck when Judy went out looking for the puppy known as Fella, the mutant then chased Judy into a ravine and trapped her there. Luckily, Fella was able to get John and Don's attention and led them to the ravine to save Judy. John shot down the creature with his laser which only left the creature unconscious. Soon after leaving the ravine, the creature awoke and ambushed the Robinsons at the crater of which the monster lived in. John was able to scare the creature off back inside its crater home, never to be seen by the Robinsons again.