This article is about a non-canonical topic in the Metal Gear series.

Lucy was a young girl placed in the care of SaintLogic research scientist Dr. Michiko Takiyama. She appeared to be timid, though in reality, she was the reincarnation of Lucinda Koppelthorn, and was bound to the EGO system.


The girl who would later be known as Lucy was one of many children bought by the SaintLogic weapons corporation for use as a test subject in the EGO project.

After the death of Lucinda Koppelthron during the Praulia Massacre, her husband Thomas Koppelthorn, vice president of SaintLogic, attempted to revive her with the EGO system. He used a synaptic nano-machine to erase all the memories within the young Lucy, including her character and identity. Once the brain was effectively a blank slate, nano-chip expansions were injected into it, and a coded synapse grew under the system's main control command. Unbeknownst to Koppelthorn, however, the core neural net produced a unique ego within Lucy's mind. Knowing that she would be killed if Koppelthorn found out, she kept this hidden. When he tried to implant his wife into her, Lucinda's memories instead merged with Lucy's new ego, becoming another conscience. Dr. Michiko Takiyama was then given the job of Lucy's caretaker by Koppelthorn.

Three years later, Lucy manipulated Koppelthorn into hijacking Metal Gear Chaioth Ha Qadesh at SaintLogic's main facility, by pretending to be a vengeful Lucinda. In reality, Lucy desired that Metal Gear's EGO system to be activated, since the nano-chip expansions implanted in her mind saw the weapon as her real body, having originally been designed to be its operating system. The EGO system's activation would allow her to merge with Metal Gear, believing it to be the reason for her existence. She planned to escape SaintLogic and activate other test subjects on her way, knowing that there were many people who would want their combat abilities.

Koppelthorn later piloted Metal Gear in battle with Snake and Venus, though he was unable to destroy them with manual control of the weapon. Reluctantly, he activated the EGO system to allow Lucy to greatly enhance Metal Gear's capabilities. However, upon gaining control, Lucy killed Koppelthorn and appealed to Snake to join her. Since Snake was a former test subject of the EGO project, she believed he had an innate desire to join with the system. Snake refused, and attacked Metal Gear with Venus once more. The two succeed in destroying it, with Lucy conceding that Snake was the stronger one, before dying.