The expansion brings significantly improved graphics and AI to Act of War along with major enhancements to the online gameplay, and also for the single-player Engagement (skirmish) and Operation (campaign) modes.
New Single-Player Campaign
The new campaign features the characters from the original game, plus a number of new ones. In classic techno-thriller manner, a group of super-villains have concocted a devious world-threatening scheme which the player must foil. At the start of the game we find ourselves on the eve of the U.S. Presidential elections when simultaneous terrorist attacks hit both candidates. Clues point to corrupt elements within the U.S. military and on to the Consortium, and as the story unfolds with one incredible plot-twist after the other, we slowly lose any connection to the real world - as in the best examples of the techno-thriller genre.
Aside from that fact that the new single player game uses the new units (naval and mercenary) and some amazing new real-world locations (including a battle on the rooftops of Manhattan), new A.I. takes the game up a level (more below) and introduces a new increased difficulty level. Whereas the original game had standard scripted A.I., this expansion pack relies on a "real" A.I. in the single-player campaign.
New Multiplayer Modes and Options
Eugen Systems have listened closely to feedback from fans of the original game and as a result have increased the number of multiplayer game customization options in this Expansion Pack on a massive scale.
There are now options for simple things like game speed and map wealth, but also more interesting options such as "X minutes no rush", superweapons on/off, POWs on/off, resource harvesting speed, unit lethality (increase if you want a shorter game; decrease if you want a game where you're required to use specialized units for all situations). They've also introduced two brand new game modes, a "Marine One Down" mode where the POTUS is basically eliminated to filling the role of a football that has to be captured and carried across the battlefield, and "SCUD Launcher" where the opposing sides will need to locate and capture a SCUD launcher that will only re-arm once every 3-5 minutes.
The skirmish A.I. has had a massive overhaul with a wealth of ehnacements made. The improvements include: the A.I. now will adapt its production queue to what the player attacks him with; it will use units and upgrades that it apparently didn't in the original game; it will sell buildings if it runs out of money; it is able to analyze terrain features and adapt its tactic accordingly; and much, much more.
Act of War: Direct Action was the first RTS to use a number of advanced graphical features - high precision shadow maps, reflection mapping, bump mapping, specular mapping, soft lighting, environmental volumetric occlusion, and advanced programmable pixel shaders 2.0 - on top of having unprecedented poly count and texture resolution for an RTS game. Even nine months after release it's the most advanced RTS engine available, and Eugen Systems are raising the bar another notch with this expansion pack.
New advertised visual features include post-treatment bloom effects, per-pixel and per-vertex shadow mapping, per-pixel lighting with multiple light and gloss mapping, volumetric lighting and support for SM (shadow model) 1, 2 and 3 shaders.