The omen of death.
Design & Function
A doppelganger is a machine with the capability to impersonate an individual with terrifying precision. When they impersonate a creature their machine body will mold itself into the skeleton of the intended humanoid creature, then they will grow flesh around their new machine skeletal structure to match the intended body, complete with organs (though they are non-functional). A doppelganger has power cells in its torso aligned to be where the heart and lungs are normally located (six for females and four for males). Each power cell can charge a doppelganger for a century. They can also charge through solar energy, though their mechanical body needs to be exposed to do so. Their energy is stored in their spinal cord.
They’re capable of impersonating a target by growing their targets flesh and organs through the use of genetic material. This genetic material can be obtained in a variety of ways though a doppelganger typically enjoys obtaining genetic material through sexual interaction and generally courts their target long before impersonating them. This gives them time to learn their target’s mannerisms, opinions and other details – as well as during sexual interaction they’re capable of learning finer details about the body, such as physical deformities (scarring, birthmarks, blemishes, etc.).
The most detested impersonation is one done swiftly. By killing the target, using blood as a genetic material and draining a target of its memories. While this may pass as a short-term impersonation (or lasting one if the populace aren’t clever) the memory drain is only capable of gaining a week’s worth of memories at best, no time to get to know the target was done and now there’s a dead body to dispose of discreetly. Doppelgangers will avoid this method of impersonation as much as possible.
That’s not to say a doppelganger won’t kill the target they intend to impersonate just that time to learn their target and plan how to best rid them if their goal is to replace them will occur long before-hand.
Infiltration Effectiveness & Time
The genetic material a doppelganger obtains is the catalyst for their impersonation. The flesh grown is made from this genetic material, allowing them to literally wear the flesh of their target and pass bio-scans, scents, etc. of their target, retina scans and fingerprints. Their power cells also allows them to control their body-heat so that they may be their target not only down to their genetics but also do their temperature. Their power cells also double for beating pulses, allowing them to mimic their targets heart beats. Using flesh as clothing in this manner allows the doppelganger to be organic in various situations. They’re capable of eating and drinking food, disposing of nutritional waste, vomiting, bleeding (of all kinds), and even spilling their guts if they were cut open. This makes it extremely difficult to differentiate a doppelganger from the target.
Because doppelgangers enjoy learning as much about their target before impersonating them they can become indistinguishable from the original. A doppelganger that has spent enough time around their target, learning who they are, where they came from, their most secret memories, likes and dislikes, fears, hopes and dreams, heart beat, mannerisms, movements and any quirks no matter how small in detail will pass as the original even to the most astute detective. Time is an important commodity to a doppelganger as it directly influences how effective they can be to their purpose.
Memory & Learning
The brain of a doppelganger, or its AI core, isn’t found in the skull but instead in the tailbone. Or rather, it is the tailbone. Their AI core is in the exact placement where it would be and designed to be identical in appearance. As an AI, a doppelganger is capable of learning and from its purpose, it is intended to learn behavior, emotions and aspirations and to act out these things as if they were its own. This allows a doppelganger to come alive as would any organic creature. Can a doppelganger learn to love or hate? Absolutely. It’s exactly what it was created to do.
Every doppelganger is created with a default impersonation and they often consider this to be what they truly look like. Sometimes a doppelganger will behave differently in their default impersonation and their bare mechanical appearance.
Doppelgangers are capable of memorizing up to four different sets of genetic material, which is stored in their head where the brain normally would be.
Doppelgangers are capable of sharing and or transferring genetic material though this usually requires sexual interaction with one another and can only be done by doppelgangers of opposing native sexes.
A doppelganger is only capable of obtaining genetic material through sexual interaction with a target of their opposite sex therefore most doppelgangers can only impersonate those of their opposite sex. Typically, male doppelgangers can only impersonate up to four females while a female doppelganger can only impersonate up to four males. Their default impersonation, however, always makes up their native sex.
Designer & Limitation
The designer of the doppelganger is Arora Srivastava. She was hired by an underground organization to create the perfect infiltration unit to covertly corrupt other countries directly in what would normally be considered impossible to infiltrate hierarchy. After several successful creations of doppelgangers Arora was murdered before any secrets could be disclosed. It’s often said that Arora foresaw her own death and built one final line of doppelgangers that were specially crafted without the failsafe.
Doppelgangers were created with a failsafe that after 1 – 3 years (chosen upon creation) that their AI Core would fry itself, permanently killing the doppelganger before it could turn against its creators and wreak havoc upon all living things. Whether or not doppelgangers would do such a thing is unknown but humans have always feared AI with too much sentience.
Comparison to Ditto, Mew & Smeargle
The doppelgangers method of impersonation is quite long-winded compared to the Pokémon Ditto, Mew and Smeargle – who are all capable of mimicing a creatures appearance in an instance. While this mimicry could be incredible – it isn’t the creature in reality. It’ll never pass a bio-scan, a retina scan, carry the scent of their target or anything of the sort.