Operation Flashpoint: Dragon Rising has a singleplayer campaign in which you are the leader of a four men squad; one player with three A.I. team members.
Multiplayer has three modes: coop, annihilation and infiltration. In multiplayer, all attachments (night vision, laser box, grenade launcher) are fully functional.
In coop, you can play the entire campaign with at least one other player, at most three. If you play with only one other player, the two empty spots in the team are being filled by A.I.
Annihilation is basically a Team Death Match mode; every player has 3 A.I.'s in his or her squad.
The pc version will have 16 v 16 players (plus 3 A.I. soldiers for every player makes 128 soldiers).
The console version will have 4 v 4 players (plus 3 A.I. soldier for every player makes 32 soldiers).