Upon starting the game players are directed to their in game bunker. There, they can view the battleground with a radar and access a limited supply of vehicles: tanks, armored support vehicles (ASVs), helicopters, jets, jeeps and PT boats. The vehicles have a limited supply of fuel and ammo, and the player can only control one vehicle at a time.
The objective is to enter the enemy's base, capture their flag and bring it back to the player's base. The flag is always located in a 'flag tower', which must be destroyed before the flag can be picked up. There may be more than one enemy flag tower, but only one of them contains the flag. Although the flag may be discovered using any vehicle it can only be carried by the jeep, which is the weakest vehicle in the game. Thus, the player must destroy the enemy flag's defenses using stronger vehicles before attempting to take it.
Source: Wikipedia, "Return Fire 2", available under the CC-BY-SA License.