Cu Chulainn is the legendary Irish hero reimagined as a Servant in the Fate series, and his Alter form presents a darker, corrupted version of that warrior in Fate/Grand Order. Fans began sharing short voice clips of his signature attacks as the mobile game grew into a large online community, using them to identify the character instantly in edits and reaction videos. Because the Alter design leans into menace rather than traditional heroism, the sound has stayed popular with creators who want a quick, recognisable cue for overwhelming power.