Sniper rifles in video games tend to show a trail when they fire, as if they used tracer rounds
. Of course, doing this in real life would be a gross violation of common sense, because it shows where the shot came from ("Tracers work both ways").
In Science Fiction
settings, expect them to fire Frickin' Laser Beams
In video games, this is intentional, to limit the sniper's power for the sake of Competitive Balance
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