SR388

SR388 is a fictional planet in Nintendo’s Metroid series. The designation SR388 is used within the games to refer to the world, which is best known as the homeworld of the Metroids. The planet first appears in Metroid II: Return of Samus (1991) for the Game Boy and has since been referenced in related materials and lore.

Geography and ecology on SR388 are described as harsh and volcanic, with extensive underground caverns, lava flows, and biodiverse ecosystems. The Metroids inhabit several life stages across the planet’s caves and grottoes, and the Chozo are depicted as having encountered and studied them there. The world’s harsh environment is a recurring setting in the Metroid II storyline and helps explain the Metroids’ life cycle and resilience.

In Metroid II: Return of Samus, the player character Samus Aran travels to SR388 with the objective of exterminating the Metroid species to prevent their spread. The mission involves navigating multiple regions, confronting Metroid life stages, and ultimately defeating the Queen Metroid in the final area. The events on SR388 are presented as central to diminishing the immediate Metroid threat in the wider galaxy, at least within the context of the game’s narrative.

Legacy and appearances: SR388 is primarily anchored in the Metroid II storyline and is cited in later installments and supplementary materials as the Metroids’ origin world. It is referenced in discussions of Metroid lore as the planet associated with the early encounters between the Chozo, humans, and the Metroid species.