The Overwatch World Cup (OWWC) was an annual international Overwatch esports tournament organized by Blizzard Entertainment, the game's developer. The tournament format had varied in each year, with the most recent one involving a preliminary stage in which national teams competed against others in a single-elimination tournament system to claim the five qualification spots in the group stages, which also included five national teams who prequalified via ranking. Top-ranked teams from the group stage advanced to a single-elimination playoff bracket at Blizzard's BlizzCon event every November. The first three World Cups were won by South Korea, while the most recent one was won by the United States.