The Metroid series chronicles the missions of space explorer, bounty hunter Samus Aran, who protects the galaxy from the enemies of the Space Pirates and their attempts to harness the power of the overpowering Metroids. The series combines the platforms of Super Mario Bros and the exploring part of the Legend of Zelda. However, the series is featured in a darker atmosphere and focuses a greater emphasis on nonlinear gameplay. The Metroid series was one of the first video games to feature a chance to explore left as well as right. You could also backtrack to areas already explored to search for secret items and paths.

The series currently consistes of twelve games that were released on almost every Nintendo video game console. The games are: Metroid, Metroid II: Return of Samus, Super Metroid, Metroid Fusion, Metroid Prime, Metroid: Zero Mission, Metroid Prime 2: Echoes, Metroid Prime Pinball, Metroid Prime Hunters, Metroid Prime 3: Corruption, Metroid: Other M, and Metroid Prime: Federation Force. Recently, Nintendo mentioned that two new games were coming to the series: Metroid: Samus Returns and Metroid Prime 4.