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It is first heard during the game's introduction sequence, and can be heard throughout the sector of the same name. A remix of Sector 1 is heard again at the end of Ending; this reprise is slow and foreboding, serving as a contrast to the otherwise triumphant and serene credits theme.
Sector 1 is included on the Metroid Prime & Fusion Original Soundtracks, titled Sector 1 (SRX) SR388 Return Area (セクター1（SRX）SR388再現エリア). It is also remixed as part of the Metroid Fusion Arranged Version medley.
A remix supervised by original composer Hamano debuts in Super Smash Bros. Brawl as a theme that plays on the Frigate Orpheon stage, as well as during the battle between Zero Suit Samus and Pikachu and the Copied Power Suits in the Subspace Emissary level The Research Facility (Part II). The usage during the Copied Power Suit battle acted as an indirect reference to the SA-X. It is also heard in The Great Maze when fighting the doppelgangers of Samus, Fox, Falco, Captain Falcon, and Snake, despite the latter four having little to no connection to Metroid.
The Brawl remix returns in Super Smash Bros. for Wii U on the Pyrosphere stage, and in Super Smash Bros. Ultimate on any Metroid stage. It is also heard during the X Parasite Spirit Battle on Lylat Cruise and the Gravity Suit Spirit Battle on Castle Siege.