Hearts of Iron III: Semper Fi

It’s time to dust off the field marshal's baton and take command of any nation in World War II; the largest conflict in history. The first expansion to the critically acclaimed Hearts of Iron III lets you take charge - or delegate - at any level, from division to nation, through a variety of scenarios. Guide your country to glory from 1936 to 1948 - wage war on the battlefields, in the factories, and at the negotiating table, in the grandest of all World War II strategy games ever made.
Features:

• Players can now define their own Theatres with a simple dragbox system
  
• The new Order of Battle Browser allows quick and easy reorganization of the entire Command Hierarchy
  
• The Command Hierarchy is now directly represented on the map
  
• A new Air Superiority map mode makes strategic air warfare easy
  
• At game start, each country now gets to choose its own hidden Victory Conditions. Can your enemies guess your secret agenda?
  
• HQs under AI control now have separate aggressiveness stances for Land, Air and Naval operations
  
• Countries can request specific actions from their allies for unprecedented cooperation
  
• Technological progress can now be shared with your allies
  
• Brigades can now be upgraded to more advanced types (e.g. Infantry to Motorized, or Artillery to Self Propelled Artillery)
  
• New 1940 scenario fills a gap in the game's timeline
  
• Hundreds of new events added to immerse players in their own versions of World War II, comparing the unfolding alternate timeline to real history
  
• Mighty warships can be designated the Pride of the Fleet, which is both an opportunity and a risk
  
• The AI has been improved in all areas, at all levels. It will defend in depth, marshal big naval taskforces and launch multi-stage invasions. It will perform more historical diplomacy and pursue a strategic production strategy