Zaroff appears to be smart at Connell's first introduction of him. He arrives on scene in evening clothes with hand ready to shake. These two descriptors are evidence of a man who has confidence and who has experienced success.
We also see this in the words of the text wherein Zaroff first speaks:
In a cultivated voice marked by a slight accent that gave it added precision and deliberateness, he said, "It is a very great pleasure and honor to welcome Mr. Sanger Rainsford, the celebrated hunter, to my home."
Zaroff obviously in his voice had a pitch, tone, vocabulary, and knowledge of content that demonstrated his intellect at his first word in this piece. This could be called indirect characterization because the author doesn't call Zaroff smart or brilliant, he shows it.
i think that zaroff is smart because of how he described the game to rainsford. he had a precise and strong tone. Rainsford is smart because of the tricks he plays on zaroff. Also, he outsmarted zaroff by leaving him a trail to follow.
In the story "The Most Dangerous Game", (which I recently read in my English Class) you can tell that General Zaroff is smart, because he set up a game, where since he is tired of hunting animals, because its too easy for him, he wants to hunt people, so he sets up Sanger Rainsford in the woods with a survival knife, etc..and plans to hunt him--and eventually kill him.
Rainsford can certaintly tell that General Zaroff is intelligent from the way that he explains his mastermind plot to him. Rainsford could tell he most likely was pretty smart also because he greets him by getting the servant Ivan away, because he intimitated Rainsford, which Zaroff was smart enough to realize, and was wearing clothing as if he was wealthy, in his big mansion, and very affable--enough to automaticly shake his hand. So right off the bat, Rainsford most likely was thinking "This guy is very smart and affable".
It is very obvious that General Zaroff shows intelligence thoughout "The Most Dangerous Game". Although in the end, he was not smart enough to win the game. Sanger Rainsford ended up winning, by outsmarting Zaroff. He jumped off the cliff, swum around the island, into Zarroffs bedroom, hid, and surprised him, and got to sleep in Zaroffs bed, while the General was killed. Rainsford thought he had never slept better.