When General Zaroff went to his bed, Rainsford was hiding behind the curtain. Then, Rainsford challenged the General. The General accepted his challenge, adding that the winner would sleep in the bed. At the story's end, Rainsford claims he had never slept in a better bed. Though not specifically stated, it is implied that Rainsford killed General Zaroff. Of course, the reader will have to decide based on what is written:
A man, who had been hiding in the curtains of the bed, was standing there.
"Rainsford!" screamed the general. "How in God's name did you get here?"
"Swam," said Rainsford. "I found it quicker than walking through the jungle."
The general sucked in his breath and smiled. "I congratulate you," he said. "You have won the game."
Rainsford did not smile. "I am still a beast at bay," he said, in a low, hoarse voice. "Get ready, General Zaroff."
The general made one of his deepest bows. "I see," he said. "Splendid! One of us is to furnish a repast for the hounds. The other will sleep in this very excellent bed. On guard, Rainsford." . . .
He had never slept in a better bed, Rainsford decided.
Here, I see the use of the ellipse as a way to challenge the reader and infer several possibilities. Most will tend to see Rainsford as killing Zaroff. What is most interesting is the last line. Because we do not know how Rainsford kills Zaroff, we must wonder what is the meaning of Rainsford never sleeping in a better bed.
Using the movie version to contrast with the short story version is a nice way to extend discourse on this ending.