One message of the story is that the strong will always prey on the weak.
Theme is the author’s message of the story. One of the themes of the story is that the strong take advantage of the weak. We see examples in this story of people who are acting outside of society, and therefore do not have to follow society’s rules. They are behaving in ways that most people would consider immoral, but once you get the upper hand you can do what you want.
You asked for literary elements as an example of this theme. Let’s look at foreshadowing, symbolism, and setting.
The conversation on the boat at the very beginning of the story foreshadows, or gives hints to, this theme and its importance well. The hunter or the hunted? Why does it matter? It matters which one you are!
"You're a big-game hunter, not a philosopher. Who cares how a jaguar feels?"
"Perhaps the jaguar does," observed Whitney.
"Bah! They've no understanding."
"Even so, I rather think they understand one thing--fear. The fear of pain and the fear of death."
This conversation foreshadows what will happen to Rainsford when he gets to the island, and also the theme in general, about the importance of the weak and the strong. Humans are used to being at the top of the hunter-hunted food chain. What happens if there is someone else on top?
Setting is the second most important literary element. Obviously, Zaroff needs a very special place to make all of this happen. Rainsford falls of his boat and finds himself trapped on General Zaroff’s island. Zaroff has made the island his own little paradise of moral ambiguity, where no one from the outside world knows what is going on. There, he is the one who decides what a human life is worth. He has determined that some lives are worth more than others. The cunning and strong deserve to live, and the weak deserve to die.
Rainsford and Zaroff have a conversation about murder and whether or not it is moral. When Rainsford finds out that Zaroff captures ships of sailors and forces them to participate in his “game” as the huntee with General Zaroff as the hunter, he calls Zaroff a murderer. Zaroff considers this view old-fashioned.
"Life is for the strong, to be lived by the strong, and, if needs be, taken by the strong. The weak of the world were put here to give the strong pleasure. I am strong. Why should I not use my gift?...”
This is one of the over-riding themes of the book, from the discussion about hunting animals on the boat to Rainsford killing Zaroff at the end. Once you have the upper hand, you take it. The strong take advantage of the weak. Kill or be killed. This is why Rainsford kills Zaroff in the end when he wins the game. His moral code, which he felt so strongly in at first, goes out the window. He has resorted to the simple concept of life is lived by the strong. He won, so he was stronger. Case closed. He slept like a baby.
Finally, there is symbolism. Many symbols can be found in this story, a symbol being an object or person that stands for something other than itself, but let’s take Zaroff’s house as an example. He is so proud of it! He says, ironically, that it means he is civilized. Why is it so important? It is so elaborate that when Rainsford first sees it he thinks it is a mirage. Look at the description.
His eyes made out the shadowy outlines of a palatial chateau; it was set on a high bluff, and on three sides of it cliffs dived down to where the sea licked greedy lips in the shadows.
It has electricity, and is described as full of lights. Zaroff invites Rainsford in and has a nice dinner with him and makes sure he is comfortable before he tries to kill him. All of this is a show of strength, and Zaroff showing all who might happen by that he is stronger than they are. The intimidation factor must be huge.
A metaphor is a comparison between two unlike things, used by the writer to add depth and description. One metaphor for this theme is related to the conversation on the boat.
The world is made up of two classes--the hunters and the huntees.
This is an important metaphor to the theme. It means that people are either strong, or weak. It does not mean that everyone is either literally hunted or hunter.
Another example is related to the setting. When Rainsford is on the boat, he notes:
It's so dark," he thought, "that I could sleep without closing my eyes; the night would be my eyelids--"
It does not mean that he could literally sleep with his eyes open. He is commenting on the fact that it is very dark and he can’t see anything. This is important to the setting, and both foreshadows the trouble he is very shortly going to be in and creates a mood.
Finally, there is a metaphor that Zaroff uses when he explains why he is such a good hunter. This falls into the 'some are stronger and some are weaker' theme. Zaroff is using the metaphor to say that his hand was “made for the trigger” to justify why he is a better hunter.
My hand was made for the trigger, my father said.
This is a segue to explaining why he can hunt humans, since he needs better sport, of course. God made him the way he is. No one can deny it.
In this most disturbing story, we explore the dark side of human nature. Rainsford eventually proves that he too succumbs to the truth that the strong will prey on the weak when, after winning the game, he kills Zaroff even though Zaroff says he will let him go. Whether or not you believe this is true, you will have to look to your heart to decide. However, if you are ever in the Caribbean, stick to your ship!