Developer Firaxis has blogged a little bit more about them, and how they ultimately plan to "rule what's left of the world" once the aliens are finished stomping on humanity.
Fortunately XCOM will be given a whole new arsenal to deal with these would-be despots, but Firaxis warn we'd better stay on top of the situation otherwise we could be overwhelmed.
"EXALT is a paramilitary secret society. Their goal is to capture the benefits of the aliens’ arrival – their genetic project for humanity and their technology – and use those advantages to rule what’s left of the world once the aliens have completed their plan and departed. And XCOM is in the way," explains the .
Expansion Enemy Within focuses more on "player-driven missions." With the aliens XCOM is at the mercy of their attacks, like abductions, and we then get to choose whether to intervene or not - the enemy decides our mission pacing. With Enemy Within and EXALT, Firaxis "wanted to change that."
"EXALT works by placing hidden cells in the Council countries. If left hidden for too long, EXALT cells will carry out a variety of operations against XCOM – Propaganda to increase panic, Sabotage to destroy XCOM’s funds, and Research Hack to cancel research progress," continued the blog.
It's here some new toys for XCOM are introduced. "XCOM can use Intel Scans, which increase in ost the more they are used, but reset to their base cost every month, to reveal EXALT cells around the world. When a cell is revealed, XCOM can select a soldier for covert ops duty, sending that soldier to the cell’s location."
"After a time, the soldier will need combat support; if this support is provided (in the form of one of our two new covert ops mission types), the cell will be destroyed and XCOM will receive a clue as to the location of EXALT’s headquarters."
"In this way, the player determines when and where (and whether!) to confront EXALT, but ignoring EXALT can lead to a lot of problems as cells proliferate and EXALT operations take their toll on the strategic situation," warned Firaxis.
The two covert ops mission types are: "Covert Data Recovery, in which the player must protect a tactical asset from EXALT’s attempts to hack it (a bit like King of the Hill), and Covert Extraction, which works like a VIP mission except the VIP is the soldier on covert ops duty, and must hack two EXALT comm arrays before leaving the map."
Check out thefor more. XCOM: Enemy Within releases on PC November 12th in the US, 15th in EU. The expansion also releases for Xbox 360 and PS3 as a standalone experience, but is yet to be dated.