Story is here if you are interested https://www.fimfiction.net/story/397060/fallout-equestria-broken-oaths
Might try to prune this a bit…
Vlyka was initially designed as an infiltration and assassin unit, built to mimic a pony and wait to strike when her target least suspects it. Her construction dates to the late War era, designed by brilliant yet disgruntled earth pony technicians to infiltrate the developing Stables and exterminate any undesirable inhabitants or staff undetected. However while her chassis and mechanics were sound, even extremely advanced for the time, the technology to allow her to operate independent of any remote control ended up prolonging the project to the point it was scrapped entirely, even her design files were nearly scrapped and her initial designation lost to history.
Decades later, Vlyka’s shell was discovered by a collection of modern researchers, who took Vlyka and her design files to study. Her premade body became the perfect testing bed for their own desired project: Truly intelligent AI, capable of fighting just as well as a soldier in any situation. Their first goal was to develop an AI that could do more than run a few pre-determined programs: they needed one who could grow on the battlefield like a pony would.
In order to let her respond to situations like a pony, Vlyka’s AI was based on a questionable technique of memory flashing: taking snapshots of a researcher’s mental state and converting it into a digital memory bank, granting a pony-like mapping for her neural pathways to develop from. The process, however, has left Vlyka with two unusual quirks: the occasional flash of data she has not herself witnessed, which appear to be memories of her mental donors, and the capacity to feel emotions.
Despite her advanced nature, Vlyka remains mostly unaware of her full capabilities. After escaping the lab under as-yet unexplained circumstances, Vlyka wandered the wastelands and set about gathering data to make sense of the world and her place in it. Vlyka struggles to process her emotions, as there is no way to easily categorize her feelings. She developed a sarcastic and dry wit which, surprisingly, is somewhat intentional despite her not fully understanding it fully.
Curious, confused and mostly quiet, Vlyka would have continued to observe civilization in silence from far away. However fate, as so often is the case, has other plans…