X-COM 2 introduces Dark Events
X-COM: Enemy Unknown was a brilliant revival of a classic strategy franchise that didn't skimp on depth for the sake of marketability. If you've been keeping up with X-COM 2 at all, you know that Firaxis Games is striving to make the game even more complex. One of the ways they are accomplishing this is through the implementation of what the developers are calling "Dark Events".
Dark Events are counter-op missions that arise dynamically throughout the duration of the campaign and deal directly with the conflict between X-COM (you the player) and ADVENT, the military organization that supports the presence of the hostile alien invaders. Early images seem to suggest that they also function as a counter-balance to the player's enhancement progression.
For example, if you've upgraded your soldier's armor at any point, a Dark Event will eventually pop up, saying that the enemy has taken note of your upgrades, and has decided to do it for their own troops to take away the advantage you hold over them. You have the chance to stop this from happening, but in true X-COM fashion, it's not that simple. The dilemma in this situation is that there are a few different options for the player to tackle, much like in Enemy Unknown, and whichever option you decide not to pursue ends up having repercussions in the future.
X-COM 2 lands February 6, 2016 and is exclusive to PC.
Quick take: X-COM: Enemy Unknown was already a blueprint for deep and emergent gameplay design, and the new Dark Events only add a new layer to that. It's clear that Firaxis is not caving to make the game appeal to a broader audience, as it continues to push complexity and difficulty as pillars of its core design philosophy. Fans of the series should be on the edge of their seats if they aren't already.