Seasonal events

Seasonal events are annual events in Overwatch. During events, a custom brawl is added to the Arcade, players can earn and buy special loot boxes and time-limited cosmetics are available. There are six annual Overwatch events in total. Events last three weeks.

Summer Games
The Summer Games were the first seasonal event held in Overwatch. In 2016, it took place from August 2 to August 23. In 2017, it took place from August 8 to August 29. There are 112 Summer Games cosmetics. The Summer Games' brawl is Lúcioball, a 3v3 game where players must knock a giant soccer ball into the opposing team's goal while playing as Lúcio.

Halloween Terror
Halloween Terror was the second seasonal event held in Overwatch. In 2016, it took place from October 11 to November 1. In 2017, it took place from October 10 to November 1. In 2018, it took place from October 9 to October 31. As of 2018 there are 190 Halloween Terror cosmetics, 21 of which are all-hero sprays. The Halloween brawl is Junkenstein's Revenge, a PvE brawl where 4 players must defend the castle gates of a modified Eichenwalde against the Zomnic army of Dr. Junkenstein.

Winter Wonderland
Winter Wonderland was the third seasonal event held in Overwatch. In 2016, it took place from December 13, 2016 to January 3, 2017. There are 124 Winter Wonderland cosmetics. The Winter Wonderland brawl is Mei's Snowball Offensive, a 6v6 snowball fight in Ecopoint: Antarctica and Yeti Hunter.

Lunar New Year
Year of the Rooster was the fourth seasonal event held in Overwatch. In 2017, it took place from January 24 to February 13.

Overwatch Archives
Archives (formerly called: Uprising) was the fifth seasonal event held in Overwatch. The Archives are a series of PvE gamemodes in the arcade where 4 players participate in a mission based on moments in the game’s lore. There are 3 missions: Uprising (2017), Retribution (2018) and Storm Rising (2019). The events ran between the following dates:

Uprising - April 11 to May 2, 2017

Retribution - April 10 to April 30, 2018

Storm Rising - April 16 to May 6, 2019

Archives 2020 - March 12 to April 2, 2020

Overwatch Anniversary
Anniversary was the sixth seasonal event held in Overwatch. In 2017, it took place from May 23rd to June 12th. There are 107 Anniversary cosmetics. It introduced rule changes to 1v1 and 3v3 elimination.