In Firepower, the player(s) take control of tanks, blasting their way through various landscapes and surroundings. Despite simulating tank combat, the game is a pure arcade game and as such the controls are very simple and intuitive. The game was popular for its frantic head-to-head combat mode and two players could face each other in a split-screen mode, attempting to be the first to conquer the enemy's territory and ultimately the opposing headquarter to capture the flag. The game featured three types of tanks, each with its own strengths and weakness, with varying balancing between speed and power. Most of the obstacles and buildings are destructible and on top of that the players had to deal with shooting turrets and helicopters chasing down the tank. The game also features a powerful map editor to create your own battlefields and levels.
Destroying enemy buildings spawned small soldiers that scattered outward from the rubble, and fled from your tank. All tanks moved faster than the fleeing soldiers, which allowed you to easily run them over for additional points. The Amiga and Atari ST versions of the game displayed a graphic "blood splat" on the ground (along with a digitized "squish" sound) when you ran over the fleeing soldiers.
Tanks could also rescue friendly soldiers that were liberated from destroyed POW camps that were scattered among the other buildings in the enemy base. Bringing the POWs back to a friendly Garage allowed them to disembark from your tank for extra points. It was also possible to accidentally run over your own soldiers.
As all tanks could also lay landmines, a popular strategy was to plant mines in an enemy base while leaving most buildings surrounding the Garage untouched. A headstrong opponent would rush back to his own base, loaded with liberated POWs. Seeing nothing amiss nor any destroyed buildings, he would assume the enemy had not found his base yet, and rush towards his Garage - and straight into the hidden landmines, killing both himself and all the loaded POWs before they had a chance to disembark.
Firepower was one of the first games to provide one-on-one gameplay via an analog modem, at speeds up to 2400bps. There was no central server or matchmaking service - you used the game's terminal software to call a friend who had a copy of the game running, and after a brief negotiation you were playing the game in the standard split-screen mode. The game could also recover gracefully from brief interruptions such as another person picking up the phone line.