ControlsThe keyboard controls allow you to fire in all four directions, while the joystick lets you fire in the direction you're traveling. This means that the keyboard controls are actually more effective for playing the game than the joystick.
GraphicsThe Composite-mode colors of the PC version are identical to the Apple version.
PCjrBoth a PC and a PCjr bootable cartridge version of this game exist. The PCjr cartridge version is differently colored.
RemakeThere is a Windows remake of the game, created for the Retro Remakes competition 2006, with the title Gridfire.
Information also contributed by Sciere