Source: Wikipedia, "Boot Hill (arcade game)", available under the CC-BY-SA License.
Boot Hill is a shooter arcade game released by Midway in 1977. The game is a sequel to Gun Fight.
A classic one or two-player western gunfight game. Each player uses a small joystick to move their cowboy up and down the play area, while a second, much larger joystick is used to aim the pistol and shoot - this larger stick also has a trigger button. The game's single goal is simply to shoot the other player, who is situated on the opposite side of the game area. Wagons and cacti litter the middle of the play area, providing temporary cover from the opponent's gunfire. These obstacles slowly disintegrate as they are shot.