Although I never declared myself a fan of this simulation, I keep coming back to it at least twice a month.So many things to learn from it ...
Decisive Action (HPS Simulations), a tactical simulation of modern division and corps-level combat designed by Jim Lunsford to teach tactics at the US Army Command and General Staff College.
Just as an example of the type of scenarios this game packs, see the following OPORD:
Scenario Background: This is a fictional scenario, taking place in Europe. For the last ten years, the REDs have claimed sovereignty of ORANGELAND's Leipzig Province. History has demonstrated repeatedly, that whoever controls the province's two major cities, Leipzig and Halle, controls the province. Escalating tensions resulted in the unprovoked REDLAND military forces (REDFOR) attack of ORANGELAND. After crossing the border, lead elements of the REDFOR 3rd Tank Army quickly seized Halle and Leipzig. The second echelon divisions were delayed by Allied airpower and are still to the East of the Elbe.
The main screen of Decisive Action. Click the image for a better view
OPERATION PLAN 01-29 (OPERATION LEIPZIG HAMMER)
Task Organization: See BLUE OOB
a. Enemy forces.
(1) Most Likely Enemy Course of Action. 3rd REDFOR Tank Army defends Halle and Leipzig with two armored divisions to retain the two key cities in order to assert sovereignty over the province. As soon as the second echelon divisions cross the Elbe, 3rd Tank Army will resume offensive operations to defeat BLUFOR and protect their territorial gains.
(2) Enemy Order of Battle. See RED OOB.
b. Terrain. See MCOO
c. Weather. The weather for the two days will be favorable for combat operations. The prevailing wind will be from the southwest at 7-10 mph. BMNT will be at 0500 hrs and EENT will be at 2000 hrs.
b. Friendly forces. See BLUE OOB for a list of CAS and other resources.
2. MISSION. On order, X (US) Corps attacks to seize Objectives NAIL and TACK in order restore the sovereignty of the province to ORANGELAND.
3. VICTORY CONDITIONS.
a. Occupy Halle and Leipzig to prevent their capture.
b. Lose no more than 30% of the BLUFOR.
4. GAME LENGTH. 15 Turns
5. SPECIAL INSTRUCTIONS.
a. At start, X (US) Corps must position all units west of PL HAWK.
b. All BLUFOR operations must take place within the X (US) Corps area of operations, marked by the blue boundaries.