Brian Posehn is a stand-up comedian and actor famous for weaving his love of heavy metal into his act, even recording a full comedy metal album. His exaggerated low bellow of Slayer comes from that metalhead persona, and clips of the shout spread through meme pages and metal forums where fans quote it as a joke salute to the band. Because it is short, loud and instantly recognisable, creators keep recycling it as a reaction sound whenever anything remotely heavy or dramatic happens.