|This article is written from the Real Life point of view|
- This article is about the theme. For other uses, see Brinstar Depths (Disambiguation).
Brinstar Depths is the theme of Kraid's Lair in Metroid (and its remake, Metroid: Zero Mission), which was also remixed in the Super Smash Bros. series. The theme was originally titled Kraid's Chamber on the Super Metroid: Sound in Action CD.
In Metroid, Brinstar Depths is an eerie and mysterious theme heard throughout Kraid's Lair. The PAL version of the game used a slower, darker version of the theme (along with the rest of the soundtrack) due to running at 50 Hz instead of 60 Hz.
A remix, titled Brinstar Depths (Melee) in later games, plays on the Planet Zebes: Brinstar Depths stage in Super Smash Bros. Melee. The remixed theme also incorporates Silence. The song was retained in Super Smash Bros. Brawl and Super Smash Bros. for Nintendo 3DS and Wii U, though its accompanying stage was not. For these two reappearances, the song was moved to Planet Zebes: Brinstar and Norfair.
Smashing... Live!, a live orchestral performance of the Melee soundtrack, featured an arrangement of Brinstar Depths (Melee) and Brinstar (Melee) titled Depth of Brinstar. To date, this is the only orchestrated remix of Kraid's Chamber.
Brinstar Depths returns in Metroid: Zero Mission, the remake of Metroid, where it is played once again in Kraid's Lair. In this remix, the ending is extended, now featuring a choir similar to that heard in Bowser's Castle in Mario Kart 64.
A brand new, metal remix of the theme, composed by Yasushi Asada, will appear in Super Smash Bros. Ultimate. It is currently unknown whether it replaces the original version, or appears alongside it. The theme was one of three to be revealed on the official website on June 12, 2018.
The original theme can be heard here:  The PAL version can be heard here:  The theme from Melee here:  The theme from Smashing... Live! can be heard here:  The theme from Zero Mission can be heard here:  The theme from Ultimate can be heard here: