It’s an age-old question: what exactly was going on when you laid waste to cartoon ducks with the Nintendo Zapper? The 8-Bit Guy is here to exhaustively explain exactly how this beautiful little accessory worked its magic. The answer is actually fairly simple. Obviously, the CRT monitor is a big dumb box that doesn’t provide feedback. The gun itself is also not particularly complex. It uses a lens that creates a very narrow focus for the light sensor located at the end of the barrel.