What do BO3 and BO5 in League of Legends mean?

BO3, two out of three. It's short for best of three. BO5, best of five. It's short for best of five games.

League of Legends game event:

Mid-season championship, global finals and all-star game are called League of Legends.

Global Finals: LOL competition with the highest honor, gold content, competitive level and popularity.

Mid-season championship: Only the champion teams in the spring playoffs in each division can be invited to participate.

All-Star Game: Players are all star players voted by the audience in each division. In addition to the main competition of the star team, there are also entertainment modes such as clone mode, unlimited firepower, two-person battle and single-player game, which is an annual feast for every LOL fan.

Intercontinental Series: Teams from 13 Division will be divided into five different competitions, facing their enemies in Summoner Canyon, competing with their main rivals and breaking old and new enmities.

Extended data:

League of Legends game mode:

Classic mode: the classic three-line 22-tower mode aims to destroy each other's crystal hub. There are only six players and two lines in the twisted jungle.

Dominate the battlefield: a game mode that focuses on competing for points on the map.

Polar Chaos: Everyone randomly chooses heroes, and there is only one line on the map. Only after death can we return to the base for replenishment and consumption.

Six-kill mode: 12 Players are divided into 6V6 duel mode.

Unlimited Firepower: All heroic skills are zero consumption, and all skill CDs are greatly reduced.

Doomsday man-machine: the computer mode of the player's confrontation skills and IMBA.

Ascending mode: the mode of competing for ascending players in the crystal seal will greatly enhance the strength of players who become ascending players.

Chaos: Fight around King Miro in the abyss of mourning, and the fighting strength of the team calling King Miro will be improved.