A Combat Cyborg (戦闘機人 Sentōkijin) is a cybernetic organism that combines living and mechanical body parts (i.e. an organism that has both artificial and natural systems) and is specifically designed for battle. They first appeared in Magical Girl Lyrical Nanoha StrikerS.
Within the Time-Space Administration Bureau's administrated worlds, the technology of cybernetic implants is commonly used to replace lost or damaged organs. However, creation of cyborgs specifically optimized for battle is prohibited by the Bureau, since the degree of body augmentation necessary to produce a Combat Cyborg requires extensive genetic manipulation. On the other hand, the Bureau allows Combat Cyborgs to be reintegrated into the society if they wish so, with their origins remaining a closely guarded secret.
Although the basis for the construction of Combat Cyborgs was developed by Jail Scaglietti 25 years prior to the events in StrikerS, the project was completed and first implemented by another (as of yet unnamed) scientist. Scaglietti and his subordinates refer to the products of this expert's work, which they see as prototypes for Scaglietti's own serial Numbers, as "Type Zero". These two groups are the only known Combat Cyborgs thus far.
The methods of creation of the Numbers are classified as Pure Culture and Clonal Culture depending on the type of genetic culture used:
- Pure Culture (純粋培養 Junsui Baiyō) refers to the method where an embryo is created through artificial insemination while using the genetic material of selected individuals (i.e. sperm and egg cells) and then genetically altered while still in its early development stages. This process brings out traits in the resulting individual that would decrease the chances of rejection when she receives cybernetic implants. Although special abilities (e.g. Inherent Skills) are rarer with this method, it is the most reliable means of cyborg mass-production. Therefore, most Combat Cyborgs are created through this method.
- Clonal Culture (クローン培養 Kurōn Baiyō) method differs in that the embryo is produced though cloning. Although it is much more expensive and has lower chances of producing a viable result, this method gives a higher chance of the Combat Cyborg obtaining the same special abilities that the original individual had.
The final product of this process is a living body whose skeleton and muscles are completely replaced with artificial implants, granting them exceptional combat ability, and whose genetic structure is altered significantly to allow this seamless meld of organic tissue and machinery. A special implant unit channels and regulates the cyborg's Linker Core output, presumably converting mana to other forms of energy and powering her internal electronics (as well as her Inherent Skills, if any). The bodies of Combat Cyborgs are grown in vats, during which time they are not aware of themselves but can be implanted with combat skills and relevant knowledge. Biological ages at which Combat Cyborgs are "activated" vary greatly, from under 4-6 for Subaru and Ginga to 13-15 for the latest Number generation.