I see you have already provided an answer. I will, however, develop it further.
Answer and Explanation:
The external events in "The Most Dangerous Game", a short story by Richard Connell, affect an internal change within the main character, Sanger Rainsford. Rainsford is a famous hunter, who also happens to be quite arrogant about his luck and position in life. He does not care about what the animals he hunts feel. Rainsford is unable to empathize with their fear. According to him, the world is divided into hunters and huntees, and he is lucky to belong to the former instead of the latter.
However, Rainsford's luck changes drastically once he accidentally lands on General Zaroff's island. Zaroff, like Rainsford, is a hunter incapable of empathy for his prey. The difference lies in the fact that the general has grown tired of hunting irrational beasts. He now hunts man. And since Rainsford sees this as murder and refuses to hunt alongside him, Zaroff decides to make Rainsford his new prey.
Of course this conflict is bound to cause Rainsford to change internally. Just like an animal, Rainsford is at a disadvantage. He does not possess a gun, while Zaroff carries one and uses hound dogs to help him in his hunt. Rainsford is now no different than one of the beasts he used to hunt. Fear of death is what drives him - the basic instinct to survive that every single animal in the world has.
Of course, Rainsford is a human being. He is rational and intelligent enough to find a way to beat Zaroff. Still, until that happens, he suffers the agony of having to run for his life, to hide in fear. The external event of becoming a prey certainly changes Rainsford into a man capable of empathizing.