Debut: Comic #13
Mother Brain is an immobile biomechanical entity that serves as the central computer system for the Space Pirates during the Metroid series. She started out as a minor character in Metroid: Third Derivative, but has since become more important to the storyline.
Not much is known about the creation of Mother Brain. It was evidently created by the Space Pirates to serve as the mastermind and defense system of their base on Zebes, but no details of its invention are currently available.
The original Mother Brain was destroyed by Samus during her first mission to Zebes. The Space Pirates immediately acted to begin building a second one during the process of rebuilding their base. It wouldn't be fully operational until the events of Super Metroid, though.
With this in mind, the existence of Mother Brain in Metroid: Third Derivative is not fully explained. While she is established to be powered by the Tourian System, a term that was also used to describe its location on Zebes, the Mother Brain of this comic appears to be an additional construct residing on Nemesis. She has yet to serve as a boss encounter, but she has regularly monitored and occasionally stymied Samus's actions.
She is currently maintained and assisted by an elite Space Pirate with the designation of TKE-215. At least, when she wants to be.
In her first few appearances, Mother Brain's involvement in the storyline is minor, and she frequently serves as filler. In order, she:
- Establishes her love for the Space Pirate general, Ridley. This affection is most certainly unrequited.
- Announces an official name change to "the MILF Brain", a decision that pleases few of her associates.
- Turns to face the opposite direction, without explanation or known physical capability.
- Plays Starcraft. (Her favorite race appears to be the Zerg.)
- After being manually turned around again, speaks in slang.
Eventually, a Logfile Filler (#244) defines her role as the Space Pirate computer system and reveals her innate psychic abilities. It also suggests that, despite her extremely erratic actions in her earlier appearances, she is capable of being very serious in regard to threats to the Space Pirates. The comic not only establishes that she is specifically programmed to give TKE-215 a hard time, but also claims that she remains in contact with Ridley, as well as a currently unrevealed entity known as (or abbreviated as) PGFGV.
Mother Brain eventually intervenes directly in Samus's mission, but her involvement is not established for a while. Her storyline begins when JD uploads Samus's pattern to a Space Pirate training simulation in #327. Mother Brain accesses this computer and, after a piratified Samus defeats a reproduction of herself at the end of the simulation, takes over the faux Samus's role.
In this guise, she attempts to convince Samus that she, in her full Power Suit, is the Chozo side of her personality, while the now suitless Samus represents her "weak" human side. She then reveals her intent to destroy the human aspects of Samus's personality through torture. Samus, however, notices that JD was trying to evacuate her from the program and makes her escape.
This leads to a sequence in which Samus narrowly avoids being killed when JD's lab self-destructs, finds JD dead in a nearby hallway, engages a Combat class Space Pirate in battle, is left completely helpless when her not-quite-fixed Power Suit relapses and eventually stops functioning, and is finally blasted into oblivion by an unexpectedly arriving Joey.
All of this, however, turns out to be a simulation created by Mother Brain. Using this and similar illusions, she intends to weaken Samus's grasp of reality. In addition, it is revealed that Samus's pattern is currently stored in Mother Brain's Tourian System itself.
Unfortunately, her influence on Samus is weakening, so she aims to have her manually deleted from her systems. To this end, she mind-controls JD, the Space Pirate with the most detailed knowledge of the Tourian System (he designed it originally), and forces him to do the reprogramming. JD successfully resists, though, and ends up weakening the system significantly, presumably stopping her from using her psychic abilities.
At this point in the story, it is unknown how damaged she is, but she may not be completely out of tricks yet.
She is incredibly whimsical in most of her appearances. She performs useless actions seemingly at random, takes joy in the suffering of others, and ultimately appears to be more of an annoyance than a threat. Still, she is fully capable of dangerous actions when provoked.
As she is biomechanical, it is difficult to tell if her treatment of other characters is due to her character or her programming. This is especially the case when dealing with Ridley. She is faithfully devoted to him, both as a commander and as a romantic interest, but one may merely be following from the other.
Whether or not she considers herself to merely be toying with TKE-215 is uncertain, but she seems to be making a deliberate effort to keep information from him on a regular basis.
In her role as a simulation of Samus, she is rather convincing. While Samus has her doubts throughout the conversation, the use of Chozoesque speech patterns and speaking of cold efficiency provide a sufficient veil that Samus doesn't know who she's dealing with at first. While her psychic ability may be responsible for this, Mother Brain appears to be capable of great deception.