Machina Development
Machina are created by corrupting humans with M2 Nanomachines. The development stages of a Machina are divided into four parts based on observed checkpoints. These are called Categories. An infected human begins at Category 1, progresses through Category 2, and finishes main development at Category 3 as a complete Machina. There is also Category 4, which is the Category occupied only by Queen-class Machina.
The Category designation only refers to the Machina's stage of development. To more accurately describe a Machina, there are the Class and Type designations beneath the Category designation.
Category 1
Category 1 refers to humans who have been infected with M2 Nanomachines but are yet to show external signs of their biomechanical nature. When a human is injected with M2 Nanomachines, there is a brief amount of time where the infection can be cured by overwhelming the M2 Nanomachines with something to counter their numbers and destroy them. However, the first priority of the M2 Nanomachines is to create the Core within the infected person's chest. Once the Core is established, the infected person is virtually incurable, and they are now referred to as a Category 1 Machina.
After establishing the Core, the rest of the Category 1 Machina's internal organs will be replaced with the standard internal organs common across all Machina Classes and Types, such as the M2 Nanomachine production organs in the breasts or the genitalia of the Machina. As the essential Machina organs are being completed, the M2 Nanomachines will also begin restructuring the body into the shape of a beautiful woman regardless of the Machina's original biological sex. Commonly, male humans keep their testicles when becoming a Machina. The body restructuring is primarily the result of the bones being converted into Machinium. When the conversion of the bones is complete, the Machina will usually stand between 180cm and 220cm in height, excluding horns and built-in high-heels. When the biomechanical organs are all complete and the body has restructured itself, the Machina's brain will be remade.
[As the brain is converted to Machina biology, the Machina will grow horns which are her link to the Cluster. The Queen-class Machina in control of the Cluster will download useful information from the developing Machina to herself, whilst deleting what she determines to be useless or otherwise unnecessary information from the developing Machina's mind. Next, the Queen will custom-tailor the new Machina's neural pathways so that the new Machina's brain is best optimized for Machina thinking and processing. Lastly, the Queen will upload a standardized database to the developing Machina containing factual knowledge and essential mental programming. When this is combined with the optimized Machina neural network, it ensures the newly-corrupted Machina thinks and acts in the ways that are most conducive to the survival and proliferation of the Machina and M2 Nanomachines. These mental changes together have the added effect of removing any detrimental mental conditions. After these changes the original entity and their personality are still present at the core of the new Machina, since the process does not affect the original consciousness.]
If there is no Queen present to do these changes, the M2 Nanomachines in the developing Machina's body will carry out the mental changes, though they will be much less optimized. With these steps all complete, the Machina then ascends to Category 2.
Category 2
Category 2 refers to the stage of development where the Machina begins growing specialized biomechanical organs and external features which allows them to be assigned Class designations. In this stage of development, the Machina's body is still a mix of human and Machina biology; mainly human muscles and skin over Machina organs and bones. To fully replace her human biology, the Machina will shift from consuming organic food to inorganic substances such as metals in order to supply her M2 Nanomachines with the necessary materials. At the same time, the Machina's external biomechanical hardware will grow. The M2 Nanomachines within the developing Machina will create this equipment for her based off her personality and physical traits. Her external hardware during Category 2 will be quite basic, but after Category 2 it can be upgraded through the use of Larvae. To assist her body in supporting itself, the Machina's spine will develop into the central part of the Machina's Anti-Inertia Systems, which significantly lighten her body and reduce the inertia of her movements. As the Machina's body progresses through Category 2, her womb will automatically create a Larva if one has not already bonded to her Core. The Machina will apply this Larva to her Core which will allow the Core to operate at maximum output as well as finishing up any remaining development, such as removing the Machina's human skin tone. After this, the Machina has completed development to become a Category 3 Machina.
Category 3
Category 3 refers to a Machina who has completed development. The maximum time required to develop into a Category 3 Machina is about 1 month, but this is shortened by injecting the developing Machina with more M2 Nanomachines or applying a Larva to her body. In addition, a few Queens are able to slow Machina development, so they can exceed 1 month as well.
Now that the Machina's body has replaced all traces of human biology, she is able to operate at 100% strength, which can include inhumanly fast sprinting and reflexes, and lifting human vehicles without issue. As such, she is vastly stronger than a Category 2 Machina. Despite her body being made entirely of Machinium alloys, the lightest Machina will only weigh about 150 kilograms in total, whilst having a mass of 15 tonnes. This is again thanks to her Anti-Inertia Systems which are permanently operating at their full capacity. Finalized development also means the Machina has much more potent breastmilk and semen.
A Machina's development now takes the form of a cycle where she upgrades one of her systems with a Larva, then attempts to become stronger through adaptation to tolerate another Larva, and so on. When a Queen-class Machina ejaculates into a Category 3 Machina it is called Blessing. In addition to receiving powerful traits belonging to the Queen, the Category 3 Machina will also receive Gyno Mode from her. Category 3 Machina must have an initial stockpile of energy to activate Gyno Mode, as it invariably consumes more energy than any Category 3 Machina can produce. Bonding with Larvae to attain additional sub-Cores is the only way to extend the limited amount of time the Category 3 Machina can remain in Gyno Mode, which is typically measured in minutes.
Category 4
Category 4 is composed of Machina who have ascended to the Queen-class by unlocking Queen-Code within the Instinct-Code of their M2 Nanomachines. The way this is done is through the accumulation of many adaptations over time and traits from other Machina via sex in a combination that is powerful enough to satisfy the evolving conditions within the Instinct-Code of her M2 Nanomachines. To unlock Queen-Code, a Category 3 Machina often may need to develop from her initial Class into a Hybrid of two Classes, and potentially into a Chimera of three or more Classes before she unlocks Queen-Code. Very rarely, an infected person naturally possesses many extremely strong traits and unlocks Queen-Code immediately. In this scenario, her M2 Nanomachines will not stop at Category 3 and will continue upgrading her until she finishes development at Category 4 as a Queen-class Machina.
Ascending to Category 4 causes the new Queen to overwrite the Cluster-Code of her M2 Nanomachines with her own, new Cluster-Code. Anything the new Queen corrupts will inherit her new Cluster-Code and subsequently belong to her. They can then spread her Cluster-Code to others, bringing them under the new Queen's control as well.
In terms of strength, the difference between Category 4 and Category 3 is the same as a Category 3 compared to a human. Similarly, Queens possess exponentially more processing power than a normal Category 3 Machina, who is already a biomechanical quantum supercomputer. A Queen's astronomically-increased ability to generate power is also enough to overcome the range issues of their natural quantum communications, allowing for limitless communication range with the Main Cluster.
Other traits exclusive to Category 4 Machina are the Queen's third eye and her Throne. The third eye, sometimes named as the Queen's Eye, is an external indication that the Queen-class Machina’s brain and horns have matured fully and have developed the processing power to be the main server of the Cluster. The Queen's Eye is not actually a Larva bonded to her head, even though it resembles one. It is a sensory organ similar to her primary eyes that may assist her with data processing. With her vast processing power and authority from her Cluster-Code, she is able to command her Cluster and learn everything her subordinates experience.
A Throne is the Category 4 Machina's equipment. It contributes power to the Queen-class Machina, rather than needing power from the Machina, and will also grant her powerful abilities. Thrones can be either Fusion-type, where they are still permanently fused to the Machina, or Vehicle-type, where they are large enough to act as a vehicle for the Queen and can be separated from her at will. Vehicle-type Thrones have a larger capacity for generating power and possess more abilities, but the Queen loses these when separated. All Category 4 Machina have access to Gyno Mode by default. Where they differ from Category 3 Machina is their ability to maintain Gyno Mode for hours as opposed to minutes.
Other Development Stages
There are a handful of unique circumstances that cause non-standard development cycles for Machina. Humans with low body mass, and humans corrupted in the absence of a Queen, are known to cause some deviations to what is described above. These are Petite Machina and Proto-Machina.
Petite Machina
Petite Machina refers to the petite style of body some Machina may have. It occurs mainly when a human with low body mass is infected with M2 Nanomachines. Most often, this is a human who is not yet sufficiently mature, but can also be due to extreme age and withering of an elderly human. If a human is not at least an adolescent approaching physical maturity, they will simply remain infected with mostly-dormant M2 Nanomachines. The M2 Nanomachines will operate on low power for long term sustainability and carry out only the bare minimum of activities, such as assisting the immune system and correcting genetic diseases. When the M2 Nanomachines conclude that the body is matured and capable of being corrupted, they will start the corruption process. This may also occur if a human who is very elderly is corrupted into a Machina. Due to having such withered bodies, the M2 Nanomachines choose to rebuild the infected human into this petite shape rather than a full-sized Machina.
Since this occurs when the infected human's body is not ideally suited to becoming a full-figured Machina, it causes the following: During Category 1, the M2 Nanomachines will still attempt to rebuild the body into a feminine shape, but the result is often a petite figure. Their breasts and upper body in general will be small, and they may only have wide, feminine hips. Their height will be approximately 150cm, excluding horns and heel-struts. These Machina will progress to Category 3 with this appearance. These Machina will be weak, and need to be nurtured by the Breeder-class Machina of the Cluster. With their help, the Petite Machina will grow into a regular Category 3 Machina with a full womanly figure. However, it is possible for the Machina to keep their petite shape as they get stronger, if the Machina truly desires it.
Proto-Machina
Proto-Machina can be thought of as having no Class at that particular time. This occurs during a certain set of circumstances where expedience is needed for Machina development. In these situations, the Machina are prevented from developing more than the bare essentials so their development is faster, but otherwise develop from Category 1 through to Category 3 as normal. This can be ordered by a Queen whose situation necessitates new forces as soon as possible, or may be triggered by Outbreak Protocol. Once the situation improves, the Proto-Machina will be released from the restrictions and allowed to develop the equipment she would naturally have.
Note: What Happens When a Pregnant Woman or Child is Infected
Pregnant human women do not experience corruption exactly as outlined above. Because corrupting them fully into Machina could terminate their pregnancy, pregnant women infected with M2 instead experience a prolonged Category 1 development, where her reproductive organs are left alone. Her Core forms, skeleton is replaced, and her brain is remade as normal for Category 1. The woman will carry her baby to term, then finalize Category 1 development and proceed as normal.
Human children do not become Machina, the M2 Nanomachines must wait for the human to mature. As outlined above, M2 Nanomachines will assess if the body is ready, and wait in a dormant state if it is not. Even a baby born from a woman undergoing corruption will not be a Machina. Instead, the M2 Nanomachines will perform their most basic function, assisting with the health of the human body, and wait until the body is big enough and progressing into at least adolescence before corruption can begin.
Out-of-story, this is to say that minors can't be corrupted and won't be lewded by us. Please respect the innocence of minors when enjoying our work of fiction.