Rachel Rhodes distinguished herself as a field tactician and negotiator in the FBI, and amassed extensive paramilitary experience in irregular warfare tactics, possibly through her work with/for Cyberdata:
During the 1970s, Rhodes served in an early Cyberdata SHOC (Special Hazardous Operations Cyborg) team, under the ID "Mother". Other members included Christian Nichols, SHOC ID "Archer" (with whom Rachel appears to have had a relationship) and Brenda Lewis, SHOC ID " Killjoy".
Some time later, Rhodes was transferred into the CIA. She was immediately put into the field and spent two years supporting rebels in third world countries, helping them to overthrow local governments and strengthening US positions around the world.
Rhodes was then assigned to a special NSC task force and sent to Egypt to provide security for a secret archaeological excavation, financed and overseen by Armand Waering. When the dig was attacked by a werewolf faction, Rachel took refuge in a nearby pyramid, but was caught in an explosion and lost both arms and most of her skin. In the same attack, an urn containing a golden symbiote (an ancient relic of the Werenation, stored in the pyramid) was smashed. The released symbiote was drawn to the injured (but still conscious) Rhodes, attaching itself to her and saving her life.
Apparently with the permission of the NSC's National Security Advisor, Miles Craven, Waering took Rhodes to his Waering Industries weapons/cybernetics labs. Waering's scientists fitted Rhodes with prototypes of highly experimental cybernetics, including hydraulic limbs and neural implants. Given Rhodes' past with Cyberdata, it's possible that she already had some such implants.
Waering erased Rhodes' memories and all records of her in computers other than his own (though he seems to have missed some of Cyberdata's records). He named the Rhodes cyborg "Mother One" and programmed her to be the key to his "Red Winter" satellite network, which was designed to seize control of the US and USSR's nuclear arsenals, as a "final stand against genocide". Waering also seems to have (maybe unintentionally) established a link between Mother One and another of his defense projects from the 70s, CAINE (Cognitive Artificial Intelligence Neural Entity), a biosynthetic CPU patterned after Waering's brain. This link which provided the cyborg with an emotional support system: Mother One imprinted herself on CAINE and came to think of the biosynthetic brain as her mother. Waering then handed Mother One bask to the NSC, where Craven put her to work coordinating a specially modified fleet of SOG (Special Operations Group) gunships.
Mother One was a sleeper agent for Waering, though: She turned on an I.O. cleaner unit that she was supposed to be leading, in order to save the members of Team 7 (in its last incarnation, under Colonel Dane) following their exposure to golden symbiotes like her own in the Balkans. Mother One then recruited the team, who took on the name WetWorks, to Waering's cause: An ongoing secret war against the Vampire Nation.
Rhodes regained some of her memories when Wetworks infiltrated a secret Cyberdata facility with the help of CyberForce member Ballistic, and when she was taken over by CAINE and used to activate the Red Winter satellites. After the latter event, in which Waering destroyed CAINE, Mother One and the Wetworks team left Waering's employ to operate as a rogue unit, then later in conjunction with I.O.
Like the rest of the team, Mother One's symbiote started changing her too. The inherent telepathic ability of the symbiotes was enhanced to the point where she could make telepathic communication possible. She also started getting controlled by an artificial intelligence called Mother. The A.I.'s objective was to make the World a more logical place by making new symbiotes and a number of agents like Mother-One to take control. The plan was foiled by WetWorks who destroyed the A.I. and saved Rachel.
In the following years, working with Wetworks, Mother One developed a relationship with teammate Grail(Joel Alonday), in no small part due to the fact that her cybernetic limbs allowed her to touch Grail in his energy-based "chi-state".
Rhodes was also taken over by the ghost of a Soviet super-psychic, named Rostov, becoming one of Rostov's "Tanagers". She was only freed from Rostov's control when Grail used his energy broadcasting abilities to "reboot" her brain/CPU (an ability that Mother One and Grail had kept secret from the rest of the team).
It is so far unclear how Mother One died, but in the wake of the WorldStorm Dane recovered her lifeless and mummified body from the ruins of an old Wetworks base. When the US Government sought out Dane and the remaining members of Wetworks, he demanded that they help him bring Mother One back online in return for his help in combating a new vampire threat. Dane also recruited a creature known as Ab-Death to help revive Mother One: Apparently Rachel's soul had not yet departed beyond Ab-Death's reach.
The resurrection had not been complete, and after a short while Rachel went into a cybernetic coma for a short time. It turned out, that a fraction of her soul was still trapped in the Land of the Dead, and along with Dane and Ab-Death she had to go there to get the last piece or she would die a final time. She retrieved the part of her soul, and learned that the symbiote she had bonded with was dead, and the symbiotes had not been created by the Night Tribe as they thought.
Mother One was last seen when she was put in a cryogenic pod. The vampire Casus bit her and turned her human remains into a vampire, and after she had freed herself, she went on a killing spree in the vampire caves, before she was caught and subdued by Dane and his soldiers.
Mother One fights alongside Wetworks once again, although she struggles to control the vampire curse in her system.