How is Piggy's death similar to Simon's in Lord of the Flies?
Piggy's death is extremely similar to Simon's in that both result from violent savagery under Jack's guidance and leadership. Although Piggy's death had a much different setting, Roger is the instigator; his action of leaning on the lever resulted in the boulder crushing Piggy. Roger also figures as one of the key instigators in Simon's mob-death, because Roger takes up the role of play-acting inside the circle before Simon enters in the dark and is killed by the boys.
In both murder scenes, the killing of each boy stems from a 'mob mentality,' whether it is the deathly dance circle which pulverizes Simon or the 'us versus them' mentality that lends Roger the confidence to lean on the lever under the boulder. If Roger had felt in any way insecure in his position, he would not have been gutsy enough to kill Piggy; but at Castle Rock, surrounded by other savages and Jack as the wild chief, Roger felt just the right amount of security that he needed to know that his foul deed would be accepted, even embraced.
Similarly, the aftermath of both deaths takes place in the sea, where the waves wash away the evidence of the boys' wrong doing. Simon's body travels out to sea, and Piggy's body is knocked over the side of the cliff and onto the rocks. Golding uses the sea as a cleansing agent in the novel, erasing the record of the boys' murderous deeds, therefore making them more easily forgotten or ignored.
Both Simon and Piggy's deaths are the culmination of unchecked savagery and violence.