Gjallarhorn comes from Norse mythology, where it is the horn blown by Heimdall to announce the start of Ragnarok, and it was brought to a new audience in God of War Ragnarok, released in 2022. Gameplay clips and trailers featuring its deep call spread across YouTube, TikTok and Twitch, where editors began reusing it as shorthand for an event too big to ignore. It remains popular because the sound instantly signals scale, danger and finality without needing any dialogue or explanation.