Gun Buster (ガン バスター), also known as Gunbuster (ガンバスター)[1] and released in North America as Operation Gunbuster, is a first-person shooter video game developed by Taito and released for arcades in 1992. In contrast to on-rail light gun shooters at the time, this was one of the first arcade games to feature free-roaming FPS gameplay, the same year Wolfenstein 3D was released on personal computers.

Gun Buster's control scheme consists of a joystick for movement and strafing and a light gun for aiming and turning. The player can also carry multiple weapons, each with different recharge rates and movement speeds, and the game's maps include walls, glasses and columns that can be used for dodging and shootouts. It also features multiplayer deathmatch modes for up to four players, between two teams, on a dual-monitor arcade cabinet.

The game's control scheme consists of both a joystick and a light gun: the joystick moves the player character forwards, backwards and sidewards in a strafing maneuver, while the light gun moves the aiming reticule and turns the character around in clockwise and anti-clockwise directions, similar to later Wii Remote first-person shooters for the Wii home console. The player's arsenal consists of a primary machine gun and several secondary weapons: mines, laser, spark, and fire; each weapon has a different recharge rate and speed of movement. There is also an invincibility shield available that lasts for 15 seconds.

The mission mode can be played either as a single-player game, or a two-player cooperative game, with the second player able to join in at any time. The mission mode mostly consists of duels with bosses, across thirteen maps. In each map, the players runs through mazes trying to kill boss opponents before they kill the player. The maps include walls, glasses and columns that the player can use for dodging and shootouts.

As the first title to run on the Taito SZ System arcade system board, the game's graphics improved on Taito's previous light gun shooter Space Gun. The graphics were also more detailed and dynamic than other first-person shooters at the time, such as Wolfenstein 3D and Blake Stone; in Gun Buster's first level, for example, players can shoot out the windows in a glass elevator.

The game's competitive multiplayer mode features a head-to-head deathmatch between two teams, predating Doom's competitive multiplayer mode. It can be played either between two players, between four players with two players on each team, or between three players with two players on one team and a single player on the other team. The arcade cabinet features a dual-monitor setup, with the second screen used primarily in the deathmatch mode, for the second, third and/or fourth players.