Mother Brain (Japanese: マザーブレイン Hepburn: Mazā Burein) is a fictional character created by Nintendo for the Metroid series. She is one of the most prominent antagonists within the series, serving as the main antagonist of Metroid and Super Metroid. Similarly named yet unrelated boss characters also appear in the games Blaster Master, Phantasy Star II and Chrono Trigger. It is revealed that she/it was created by the bird-like Chozo species. Mother Brain has been killed multiple times by series protagonist Samus Aran.
Source: Wikipedia, "[en.wikipedia.org/wiki/Mother_Brain Mother Brain]", available under the CC-BY-SA License.