Gun.Smoke is a vertical scrolling shooter that casts the gamer as a lone gunman, out to save the gold rush town of Hicksville from a fearsome group of bandits known as the Wingates. Each level has a particular target enemy, although his henchmen must also be taken out.
The gameplay is similar to Commando, with diagonal-down action and enemies coming at you from the edges to be shot or avoided. Power-ups can be grabbed along the way, such as finding a horse that allows the player to get hit twice before death instead of just once. There are also scenes in which the cowboy rides a river and uses a railway line.
The NES version has different controls compared to other versions, with the A button used for firing up and right, the B button for firing up and left, or using both buttons simultaneously for straight ahead shots. One-button control systems work similarly to this.