Firaxis revealed today that they, and parent company 2K Games, will be at the PC Gaming show this Monday with something related to XCOM 2. Before we get into looking at what that is, let's take a look at the teaser here:
As you can see, we have the name and a potential subtitle, as well as a reminder of when the PC Gaming Show happens. Given that XCOM 2 had you taking over a resistance movement to fight off the alien invasion when they had conquered Earth and they were using stealth as well to conceal their intent, the title "The Real War Begins" could easily infer that things are heating up. This could function as a continuation of the main campaign, or in a more traditional Firaxis style, it could take place in an alternative path much like how XCOM: Enemy Within functioned for the first game of the reboot—someone took a different action and thus a new set of base assumptions needed to be made.
The last time we heard from XCOM 2 was when the officially supported Long War 2 mod by Pavonis Interactive was released. While friendlier than the first game's Long War mod from the same team, it lengthened out and added new challenges to the game, and worked with the pieces of DLC that had already been released. Those DLC have been found by some to be a bit meager in some cases, in particular Anarchy's Children and Resistance Pack Warrior have negative reviews for being cosmetic; the larger Alien Hunters has mixed reviews due to users feeling it breaks core assumptions; and the best received one, Shen's Gift, is positive but critiqued for its price tag. Firaxis games typically have at least one large expansion, like XCOM Enemy Within, or are similar to the Civilization 5 expansions.
One additional note is that the Steam Depot for XCOM 2 has seen numerous updates recently (as recorded by Steam DB), which reveals developers tweaking aspects of the game on Steam. A large expansion would likely need a lot of work on textures or files in the game already, especially if it's going to be released soon after the conference.
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