However, as part of this, a French theater chain put out a teaser image claiming that a new hero would be unveiled.
The theater has since claimed this is a case of egregious typos or whatever and definitely not true, but for the sake of discussion, let's say they're lying and look at who it is most likely to be.
To note, I didn't come up with any of this, but am just compiling this here in story format because it's more fun. The links are all at the bottom, with images embedded as we go.
1.) Blizzard has said they're currently testing two new heroes, and implied they're either a Support and a Tank or two Supports.
2.) The map this short takes place on is Dorado. This gives us our first clue. Way back in November, people noticed that there's a table in Dorado with files for Soldier 76/Jack Morrison and Sombra. Given Soldier 76 is Jack Morrison, this only leaves the mysterious Sombra file, which would fit with a Soldier 76 vs. Sombra animated short.
As an addendum, it's worth noting they've teased unreleased characters in maps before, such as D.Va on Hanamura:
3.) As new maps were added into the game during the Spring, pictures of a mysterious hooded figure, sometimes with the name Sombra attached, started appearing in other new maps such as Route 66, and we started getting a much better picture of her:
4.) Reaper has a dialog line that says "Where is Sombra when you need her?" This implies she's a field agent and presumably a villain, something the game is rather low on (there are only five right now between Reaper, Widowmaker, Junkrat, Roadhog, and Symmetra).
5.) In the first GameSpot Overwatch video, there's a sniper scope with a similar symbol to the one on Sombra's mask.
6.) In a later GameSpot video (I think), they really messed up and actually have her in the character selection screen and you can see she's in the Support section.
7.) And today, Blizzard put up a teaser for their Soldier 76 video saying it takes place on Dorado, and someone who is very plausibly Sombra is in the teaser image.
8.) Some people seem to think that Sombra is Pharah's mother given she has some similar clothing elements like the jacket collar and is also a sniper. Pharah's mother is supposed to have died at some point in the past, but Jack Morrison (Soldier 76) and Gabriel Reyes (Reaper) were also supposed to have died in Overwatch's civil war, so it's entirely plausible she """died""" in the same event. It's worth noting that Reaper wears his exact same old outfit, but with a black trench coat and mask added, and it's very Blizzard like to use the exact same plot gimmick on three separate characters, so this isn't an entirely implausible theory. I've included an image of the old Overwatch group below if you want to make comparisons.
Since people keep asking about Symmetra as a villain, see this comic:
As well as this statement from the game's director:
Jeff Kaplan: "Symmetra is kind of a villain, but she kind of thinks she’s doing the right thing."