There were a few large scale battles I was in with planes, tanks, and helicopters that rivaled Hollywood style war movies but for the most part things are pretty low key with small skirmishes here and there. Downloading these take only a few seconds and it's off you go.
A really slick feature of the game allows you to create custom missions on the fly in the editor and test drive them in co-op play. That's not because people aren't playing co-op - oh they are - they are playing custom missions and mods with 50+ players. Hopefully you have a set of pals lined up to play though, because if you go looking for people to play online you won't find them. Each player can gear up to a specific role and pick their own loadout of weapons, and while it's wise to stay in formation players are free to roam anywhere. Tactical games are built for co-op, and ArmA 2 is no exception to the rule. The game's campaign can be played online or via LAN in a four player co-op mode.
