Holy Diver began as the title track of Dio's 1983 debut album, written around a dark fantasy figure travelling through a dangerous world. Killswitch Engage later recorded a heavier, faster metalcore version that kept the central riff and chorus while replacing the original's classic metal polish with shouted vocals and down-tuned guitars. That cover spread through metal playlists, workout videos and gaming edits, where its instantly recognisable riff worked as shorthand for intensity. It remains in use because the hook is short, aggressive and easy to recognise even out of context.