I feel that the littlun with the mulberry-colored birthmark is responsible for the destruction of the boys because he perpetuates fear amongst them. In Chapter Two, the littlun with the mulberry-colored birthmark asks Ralph what he is going to do about the "snake-thing." The littlun claims that the "beastie" came in the dark and will return that night. Ralph denies the existence of any "beastie" and dismisses it as just a nightmare. However, mentioning the "beastie" initiates fear throughout the group of boys. One of the many themes throughout the novel deals with how irrational fear can result in the collapse of reason, structure, and morality. The boys become plagued by the fear of an unknown beast, and take drastic measures to feel safe. Jack uses this fear to boost the status of his hunters as "protectors," and Simon loses his life after being mistaken for the beast. This fear gradually possesses each of the children and drives the majority of the boys towards savagery.
Jack is obviously instrumental in leading the boys towards destruction. Jack usurps power and persuades the majority of the boys to join his tribe. Jack's tribe encourages violence, savagery, and immorality. Jack is indirectly responsible for the deaths of Simon and Piggy, and attempts to murder Ralph. Jack is a heartless tyrant who has no regard for morals or authority. The boys who follow Jack are brainwashed and become barbarians who value violence and carnal passions.
Samneric are partially responsible for the destruction of the boys on the island. They abandon the fire, which goes out, as a ship passes the island. The ship could have possibly rescued the boys. If the boys were rescued, then Simon and Piggy would still be alive, and they would not have descended into barbarism. They also claim that they saw the beast, which was actually a dead paratrooper, and are indirectly responsible for Simon's death. After they tell the news of the beast's existence, the frenzied boys mistake Simon as the beast coming out of the forest and brutally murder him.