Mother Brain
The monstrous brain controlling the Space Pirates from within a jar.
Mother Brain is a fictional character created by Nintendo for the Metroid series and serves as one of its most prominent antagonists. Originally designed with a milder appearance resembling an "old lady living in an apartment complex" by Hiroji Kiyotake, her final form was altered by Tomomi Yamane to feature a more monstrous look with dripping saliva and foul breath. She typically appears as a large brain seated within a jar or glass tube, from which she controls the Space Pirates on the planet Zebes. In the original Metroid (1986), she lacks a single large eye; that design debuted in Super Metroid (1994). Mother Brain is best known for being killed multiple times by the series protagonist, Samus Aran.
- Weakness
- In Metroid NES, Mother Brain is vulnerable to any weapon, but the most effective strategy is to use missiles, as the Ice Beam does not exist in this game. Power Bombs do not exist in the original.
Lore & Background
Mother Brain takes the form of a massive brain situated in a glass tube, often featuring cybernetic spikes. While her standard depiction involves being contained, the Super NES version of Super Metroid reveals a separate mechanical body she controls, not a bipedal form of Mother Brain herself. Hiroji Kiyotake's initial concept for this design was an "old lady living in my apartment complex," but Tomomi Yamane expanded upon it to create a filthy appearance with dripping saliva and foul breath. In the original Metroid, she utilizes the Metroid species as weapons before being defeated by Samus. She is subsequently rebuilt for Super Metroid, where she reveals a new, much larger form at the end of the game that nearly kills Samus. The Galactic Federation later constructed biomechanical supercomputers called Aurora Units, which are explicitly stated to be based on Mother Brain's technology—not directly stated to be Mother Brain herself. Additionally, an android named MB in Metroid: Other M is partially constructed from her DNA.
In Their Own Story
In the original Metroid, Mother Brain serves as the central antagonist utilizing Metroids against Samus Aran until she is defeated and rebuilt for Super Metroid. During the climax of Super Metroid, her larger form nearly kills Samus before a Metroid that imprinted on Samus sacrifices itself to protect her. This Metroid drains energy from Mother Brain and transfers it to Samus, allowing the bounty hunter to defeat the antagonist and escape. In Metroid: Other M, the scene of Mother Brain destroying the baby Metroid is reenacted in an FMV cutscene. She also appears as a primary antagonist in Captain N: The Game Master, where she serves as the archenemy of Kevin Keene. A reimagining of the character voiced by American singer Levi Stubbs appears in the series and its related comic book media.
Reader's Guide
To defeat Mother Brain, players must first break the glass tube containing her to access the brain itself, though she assumes a bipedal form in Super Metroid. Since Super Metroid (1994), she is characterized by having a single large eye. Her final encounter in Super Metroid involves a massive new form that requires Samus to utilize energy drained from a sacrificed Metroid to survive and win. In Captain N: The Game Master, she acts as the primary antagonist. Mother Brain also functions as a summonable helper character known as an "Assist Trophy" in both Super Smash Bros. for Nintendo 3DS and Wii U and Super Smash Bros. Ultimate. Her design evolution from Osawa's human-like concept to Yamane's monstrous version is a key aspect of her visual history.
Did You Know?
- Mother Brain was originally designed by Hiroji Kiyotake to look like an "old lady living in my apartment complex".
- Tomomi Yamane altered the design to include dripping saliva, foul breath, and a filthy appearance.
- In the original Metroid (1986), Mother Brain does not have a single large eye; that depiction began with Super Metroid (1994).
- She was voiced by American singer Levi Stubbs in Captain N: The Game Master.
- IGN ranked Mother Brain as the 9th best video game villain.
Frequently Asked Questions
Who is Mother Brain?
She is a fictional antagonist created by Nintendo who commands the Space Pirate organization from their headquarters on Zebes. Initially designed to look like an old woman, her final form became a monstrous brain inside a glass jar.
What are Mother Brain's weaknesses?
In the original NES game, Samus must use Standard Missiles and Power Bombs to defeat her during the boss fight. Later in Super Metroid, she becomes vulnerable specifically to Super Missiles after being stunned by a Power Bomb.
How does Mother Brain's story end?
She is ultimately destroyed by Samus Aran, which frequently triggers the self-destruct mechanism of the planet Zebes. Although her physical form is eliminated, clones or copies of her consciousness appear in later entries like Metroid Fusion.
Why is Mother Brain important to the series?
As one of the most prominent villains, she orchestrates the breeding and weaponization of Metroids for the Space Pirates. Her defeat marks a major turning point in Samus's journey across multiple games.
What does Mother Brain control on Zebes?
She acts as the central AI that directs all Pirate activities and monitors the facility from within her containment unit. This includes managing security systems and overseeing the creation of biological weapons like the Metroids.
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