Henshin is the transformation command long associated with the Kamen Rider franchise, the Japanese tokusatsu series that began in 1971, where heroes use belts and devices to change into armored forms. Unhenshin reverses that idea, marking the return to a normal state. The Legend version of the cue spread through fan edits, soundboards and short video posts shared by tokusatsu fans online. Its popularity comes from how specific it feels compared with a generic power-down noise, so creators keep using it whenever a transformation, upgrade or dramatic entrance needs to be undone.