RNG, short for Random Number Generator is used to generate events that seemingly have no pattern to the gamer. It may be implemented by both physical hardware devices or software programs. RNG in a game.
Random number generators or RNGS are hardware devices or software programs which take non-deterministic inputs in the form of physical measurements of temperature or phase noise or clock signals etc and generate unpredictable numbers as its output.
In fact, they have one of the most diverse arrays of horror hits, including films by vets like Tobe Hooper and Dario Argento, alongside newer films from indie studios.