Metroi (メトロイド, Metoroido?) is a series of science fiction adventure video games produced by Nintendo. The series was conceived by longtime Nintendo designer Gunpei Yokoi.Metroid combines the platforming of Super Mario Bros. and the exploration aspect of The Legend of Zelda with a decidedly darker atmosphere. It is noted for having one of the first female protagonists in a video game, and for its nonlinear gameplay. Metroid chronicles the missions of bounty hunter Samus Aran to protect the galaxy from the depredations of the Space Pirates and their attempts to harness the power of fictional organisms such as the eponymous Metroid against civilization.