Blizzard's "Overwatch" is one of the more popular game franchises it has right now, and part of that is because they've been making putting a lot of effort into making the universe as vibrant as it could possibly be. That means in addition to great gameplay, the lore is very deep, and there's interest in both aspects of the game.
Blizzard has been teasing the addition of new character Sombra to "Overwatch" for a while now, and original rumors hinted toward Sombra being the character that would eventually be Ana, the sniper mother of character Pharah. This time, however, it seems as though they're finally pushing through with putting her into the game after all this time.
According to Polygon, a distorted image of who is being claimed to be Sombra has been posted to Imgur, Gyazo, and DeviantArt, among other sites, purportedly an internal Blizzard leak. (According to Reddit, however, it's from a Russian "Overwatch" group.) It's likely that Blizzard feels that it's already the right time to reveal Sombra, as the ongoing search for her involved a mysterious alternate reality game that involves a lot of hacking, editing, and decoding encrypted images and audio. "Overwatch" director Jeff Kaplan also did say that a new hero is pretty much ready to roll out.
In the image, Sombra is revealed to be wielding a submachine gun, but other than that there are no clues as to what her abilities are. Sombra's bio says she worked with the Mexican Los Muertos gang of outlaws until she took on too much heat and had to lay low underground and keep a really low profile. (Sombra does mean "shadow" in Spanish, after all.) It's possible that she joined Talon, the same organization Reaper and Widowmaker, other "Overwatch" characters are in.
There's also reports of a new game mode coming to "Overwatch," possibly a Halloween-themed event. All we know for now is that Junkrat is dressed as a mad scientist called Junkenstein, and there are three stages.