http://www.arma2.com/arrowhead/arrowhead.html
FEATURES
2 NEW GAME ENVIRONMENTS
Takistan: 160 square km of Central Asia modeled with extreme
precision using real world data
Zargabad: 70 square km of extremely realistic environment
including full areas of dense urban CQB confl icts.
DEEP STORYLINE
The chance to enlist in various roles within the US Army from
basic infantryman to pilot and tank crew.
NEW FACTIONS
Amazing variety of local army and guerrillas.
NEW WEAPONS AND VEHICLES
AH-64 Apache, MH-47 Chinook, AH/MH-6 Littlebird, Stryker
variants, M3 Bradley, T-55, BTR-60, M113, UH-1H, FN FAL, FN
SCAR variants and many more.
ARMA II WARFARE MODE
Improved large scale multiplayer experience with elements of
real time strategy gameplay.
STANDALONE RELEASE
Operation Arrowhead does not require the original ARMA II.