Ivan is an enormous man who not only acts as a sort of butler to Zaroff. He answers the door to the lost on the island and makes sure that they are well taken care of. His brings out the food and prepares the rooms for guests. He watches over the latest captives and prepares Zaroff and the others for the hunts. Ivan is not just a house boy to Zaroff, he is employed to do anything that is asked of him including torturing and killing any person who does not agree to play the game.
Ivan ends up meeting his demise when Rainsford sets a trap for him because Zaroff asked that Ivan help him hunt down this worthy adversary.