Muzzle Flash refers to the ignited gas cloud that appears at the end of a gun's barrel when firing. This will get noticed very easily by experienced players and Noobs alike. In order to reduce the muzzle flash, an S3 Suppressor can be attached. Some guns in the game has flash suppressor built into the gun, which inherently reduces muzzle flash (doesn't seem to have any effect in many cases). Covering this flash can help camping snipers from the opponents figuring out their exact location.