I do not own the Fallout series, but I do own this fanfic and I genuinely hoped you liked it as its come together these past few months.

AN: Here we go.

Synths

We all know what robots are. Machines that can perform tasks with little need for human intervention. Most do not resemble humans and the few that do, do so in only the vaguest approximations of human forms. Even rarer than humanoid robots are robots who act human. Robots that, for whatever reason, have grown beyond their programming. Robots that have embraced human concepts such as morality, self-determination, creativity. Despite this rare phenomenon, here have always been distinct, inconsolable differences between beings of metal and beings of flesh.

Then the Institute created the Synths.

Synths, or rather Synthetic Humans, are exactly as the name implies. Robots that have been designed to purposely imitate humankind. To better understand the Synths, we must understand the organization that created them: The Institute.

Formed from the remnants of the Commonwealth Institute of Technology in Cambridge, Massachusetts, the Institute was a clandestine organization that preferred secrecy and isolation instead of open cooperation with the rest of the Commonwealth. They limited their exposure to the occasional scavenging party, composed of heavily insolated personnel and third-party mercenaries. This level of secrecy wasn't enough for them, however. Despite their technological wealth, their numbers were limited and losing personnel on topside missions was a risk that could not be taken lightly.

And so, the Institute began working on an alternate solution. Robotics was the obvious answer, agents who didn't need food, water or sleep, who couldn't betray their superiors or disobey orders. Unfortunately for the Institute, as advanced as many robots are they lack the… elegance for missions of delicate nature. In layman's terms, they're clumsy.

When it was apparent that no current robot was suitable, the Institute began designing their own. And so, the first generation of Synths were created.

First Generation Synth

The First-Generation Synths (referred to as Gen-1s) were the offspring of the Institute's first foray into humanoid robotics. Modeled after the human skeleton, Gen-1s revolutionized android technology. Their slim, human design gave them a precision and grace that no previous robot had ever had. The skeletal chassis is made from lightweight alloys that give them a compact form. Most of their mechanisms are stored inside the chest cavity and (in a bit of grim humor) are shaped to resemble internal organs. The optic sensors, voice module and central processor were stored in the skull-like head. Their minimalist limbs were articulated by a series of tensile fibers that simulated muscle action.

These Gen-1s proved themselves as simple, but effective agents. Cheap and easy to mass-produce, they fulfilled tasks from maintenance, custodial work to scavenging. They also proved themselves as fairly capable soldiers. What they lacked in individual skill, they made up for in numbers that provided overwhelming firepower. Their programming included basic guerrilla tactics and their databanks had facial recognition software to identify Institute personnel.

However, they were still very flawed. Their chassis were frail and most of their internal mechanics were left exposed, though this could be corrected with body armor. They also had programming problems, specifically in regards to their navigational software. Glitches occasionally caused them to repeatedly crash into walls. Their skeletal forms and stiff gaits also made them poor infiltrators.

Second Generation Synths

With the development of Gen-1s, the Institute attempted to work with the settlements of the wasteland. Using the Gen-1s as representatives, they were sent to attend a meeting of the Commonwealth Provisional Government, an attempt to unite the settlements of the remnants of Massachusetts. What happened after is anyone's guess, whether the Synths were attacked on sight, malfunctioned or just ordered to attack is a mystery. All that is known is that the CPG disbanded and the Institute returned to underground living, more agoraphobic than ever.

Following the Massacre of CPG, the Institute worked to make its Synths more human-like, to…mixed success.

The Gen-2s were given software upgrades that improved their navigation systems as well as combat mechanics. The most notable upgrade was to the chassis, however. An internal mesh was grafted over the chassis to increase ballistic damage and to support a thick layer of artificial 'skin' that was made from plastics. The result was a more effective solider that was marginally better at infiltration. Even if they did look like waxy nightmarish mannequins.

Generation Three Synths

Despite the improvements of the Gen-2s, they still weren't perfect. While the Institute maintained a stature of absolute secrecy, they were still dependent on resources from the surface. This, the fact that some experiments simply weren't feasible underground, and good old-fashioned hubris resulted in a need for the perfect infiltrator, a synth that was nigh-indistinguishable from human: the Gen-3 synth.

With the use of pure, unmutated human DNA and the FEV virus, the Institute created synthetic flesh. No longer metal and plastics in a crude caricature of the human form, but flesh, hair, bones, blood. Perfect copies, but copies nonetheless. The chip inside their head that gave then a direct connection to the Institute was all that remained that connected them to their predecessors.

With the creation of the Gen-3s, the need for risking valuable personnel had been reduced. Now the Institute could send disposable Gen-3s to the surface without the fear of exposure or loss. Or so they thought. One of their Synths was exposed after a malfunction that resulted in the deaths of several citizens of Diamond City. The malfunction, now referred to as the Broken Mask Incident, revealed the creation of the Gen-3 to the Commonwealth. Now that Synths could look indistinguishable from humans, there were no limits to what the Institute could do. A wave of paranoia swept over the 'Wealth, as people feared they or their loved ones could be taken and replaced with a Synth double.

And more than a few of them were.

The Gen-3s were a complete success in all but one regard. They were too human. Overtime, many Gen-3s would develop their own identities, hopes, dreams and many would attempt to escape the Institute to forge their own lives. It should be no surprise of course. If something as inhuman as a ZAX can come to the conclusion that it has a soul, it was only inevitable that a near-perfect copy of a human being would reach the same conclusion. The bigger surprise is for how long the Institute kept deluding itself to this fact. They made something that looked, talked, and walked like human, should it be any surprise it would want to be human? In simpler words, the Synths walked like the humans until the humans walked like them.

Synths Trivia

Gen-3 Synths are known to be fond of Fancy Lad Snack cakes.

An elite force of Gen-3 Synths was formed to hunt and retrieve damaged, kidnapped or escaped synths. These Gen-3s were called Coursers.

A group of Synth sympathizers were formed to help runaway Synths escape the Institute. They called themselves The Railroad.

Two prototype Synths were created to bridge the gap between Gen-2 and Gen-3. Mechanical in nature, with a rubber-like skin covering, these two Synths escaped to the Wasteland. One created a safe haven for Synths in an abandoned observatory near Far Harbor, dubbed Arcadia. The other started a private detective agency in Diamond City.

With the destruction of the Institute in 2288, the future of the Gen-3s remains uncertain. They have gotten the freedom they so desired, but at the cost of their species. With the Institute's destruction, so too were the secrets to creating Gen-3 synths lost.

Like Ghouls, Gen-3 Synths are treated with suspicion at best and outright xenophobic hostility at worst. Time will tell if they'll ever find a place in the contested land that is the Wasteland.

With that, this Bestiary is complete and I would like to thank everyone who had read and supported it. The Wasteland is cruel and at times, the people are crueler, but I am grateful that so many have taken to my work. I have much more to so you, I promise.

- John Bones