Luigi (Japanese: ルイージ, Ruīji) is Mario's younger, taller, thinner twin brother. He is a major protagonist of the Super Mario series. Luigi has helped and fought alongside his brother on many occasions. Throughout his life, he has lived in Mario's shadow, developing both cowardly and heroic tendencies. Mario Bros. marks his first appearance in the Mario series and his debut in general. Originally a palette swap of Mario, Luigi was created to facilitate a second player option. Since the two-player mode was dropped from most main Super Mario games beginning with Super Mario Land, Luigi has gained his own identity and personality. This is especially noticeable in installments for the Luigi's Mansion series of games, as well as the Mario & Luigi series.