Metroid Fusion (メトロイドフュージョン?) is an action-adventure video game published by Nintendo for the Game Boy Advance. It was released in North America, Europe, and Australia in November 2002, and in Japan in February 2003. The game is the fourth main installment in the Metroid series. Metroid Fusion was developed by Nintendo Research & Development 1, the same development team that created the 1994 video game Super Metroid for the Super Nintendo Entertainment System, which visually bears a resemblance to Metroid Fusion. Elements that are similar in both games include the gameplay, screen layout, and controls, albeit with minor enhancements.
Chronologically, Metroid Fusion takes place last in the fictional Metroid universe. The story centers around bounty hunter Samus Aran, who is sent by the Galactic Federation to the Biologic Space Laboratories space station to investigate an explosion. There, she learns that the station is swarming with organisms infected with X Parasites, virions that can replicate their hosts' physical appearances and memories, killing them afterward. Learning that the Galactic Federation plans to capture the X Parasites for further study, Samus must destroy the space station to protect the Federation from the underestimated destructive power of the X Parasites.