|This article is written from the Real Life point of view|
The Space Pirates battle theme first appeared in Metroid Prime and later was remixed in Metroid Prime 2: Echoes, Metroid Prime Pinball, Metroid Prime 3: Corruption, and Metroid Prime: Federation Force. In the Metroid Prime & Fusion Original Soundtracks, this theme was titled VS. Space Pirates (VS.スペースパイレーツ). The Echoes version is included with the Samus Archives Sound Selection CD.
The Space Pirates theme is frantic and shrill in tone, befitting the aggressive nature of the evil Space Pirates who attack Samus Aran on sight. Each version has a different mix to it. The Echoes version adds extra drums, and overall sounds darker and less shrill. The Corruption version is once again shrill but adds orchestral instruments to make it sound more dramatic.
In Prime, the "Pirate Yoin" theme often plays after battles with Space Pirates. Before the first battle with multiple, non-injured Pirates at the entrance to Glacier One, a alternate version of this theme's tense introduction can be heard in the Specimen Storage room. In Echoes, the Pirate Fear theme plays instead, with Pirate Encounter Prelude playing before Pirate battles. In Corruption, the Ship Down theme sometimes acts as a prelude to the Pirate battle theme.
In Metroid Prime Pinball, a remix of the Space Pirates theme is played during the Space Pirate Panic minigame. This version is comparatively subdued and less shrill, and its second half consists entirely of percussion.
In Metroid Prime: Federation Force, the theme is occasionally remixed, with echoes heard sprinkled throughout the soundtrack. These versions are arranged as orchestral militaristic marches. Two notable full-length remixes are heard in the Shooting Range (which features targets with Space Pirate likenesses) and M22: Convergence. An alternate version of the Shooting Range remix is also part of the credits medley.
The theme from Prime can be heard here: , the theme from Echoes here: , the theme from First Hunt here: , the theme from Pinball here: , the theme from Corruption here: , the Federation Force shooting range theme here: , the Federation Force M22 theme here: , and the Federation Force credits theme here: 
- The theme sounds similar to the track "Futile Escape" from the movie Aliens, a film which some Metroid games have taken plot inspiration from.
- Aspects of the theme can be heard mixed into the Mystery Creature's battle music and Nemesis Ridley in Metroid: Other M.