According to Zaroff, the most dangerous game is Humans. Humans have intelligence and cunning that typical game animals lack. Humans can fight back in a way that typical game animals cannot. This difference in capability intrigues Zaroff, and makes for a much more "entertaining" hunt than typical hunting does.
Rainsford proves this over the following three days. He sets a trap, using a flexible tree as a spring to stab an unsuspecting victim. The trap kills Zaroff's aide, Ivan. Rainsford kills one of Zaroff's hounds with a "Burmese Tiger Pit." Ultimately Rainsford kills Zaroff, proving that a man is very dangerous game.