Berserk began as a classic role playing game status where a character gains strength but loses control and attacks automatically each turn. Final Fantasy V helped popularize that version in the early 1990s, and the idea spread through later RPGs, anime fights and gaming culture. Online, creators borrowed the roar and rising intensity as shorthand for rage mode, using it whenever a person, pet or character suddenly snaps. Its meaning needs no explanation, which is why it still works in short edits and streams.