A game system causes an enemy character that is caused to battle with a player character to appear by implementing a first lottery, and implements a battle between the enemy character that has been caused to appear and the player character. After the battle has started, when a player has performed an operation input that selects one item among a plurality of types of items for acquiring the enemy character, the game system implements a second lottery based on the win probability that corresponds to the type of the selected item and gives the enemy character with which the player character has battled to the player when the player has won the second lottery.