Rise of the bots: Bot prevalence and its impact on match outcomes in league of Legends

League of Legends is a multiplayer online battle arena game where features are unlocked as players level up their accounts. Because it takes a significant amount of time to reach the max level, there exist accounts that are leveled automatically by illicit “bots” and then sold on the market at the max level. These bots participate in matches like human players but are incapable of either playing intelligently or cooperatively with teammates. This paper presents an investigation into the prevalence of bots in player-versus-player match types and their impact on match outcomes on the North America and Europe West servers, using the data gathered through the Riot Games official application program interface. We demonstrate that bots are present in all major match modes at various levels and that they negatively influence the balance of matches on both servers.