Blizzard released a brand-new event today for Overwatch. Overwatch Uprising introduces new skins, new sprays, new player icons, new voice lines, new highlight videos, new emotes, and an all-new cooperative mode that takes you into the past on Tracer's first mission with Overwatch.

It's you and three friends going against the omnic uprising in King's Row. There are various objectives to complete throughout the map and it will deliver quite the challenge, especially on the higher difficulties.
Celebrate the Overwatch Legacy

There are other changes and adjustments that were made today in the big update. The full list of changes can be found over at the Battle.net forums.