Luigi is Nintendo's green-capped younger brother of Mario, first introduced as a second player in the arcade game Mario Bros. and later a star of the Super Mario series, including Luigi's Mansion. His distinctive voice became a defining part of his character across decades of games, cartoons and fan videos. As short game audio spread on soundboards and social platforms, his catchphrases and reactions were clipped for memes and edits, and they remain popular because they instantly signal playful panic, reluctant bravery and classic Nintendo nostalgia.