阿纳斯塔西娅·尼古拉耶芙娜·罗曼诺娃(1901年6月18日– ？) 是一位俄国公主，沙皇尼古拉二世最小的第四个女儿，罗曼诺夫家族最后的幸存者。她偷渡到德国后，化名为安娜·安德森（Anna Anderson）。
Realizing that something must have happened to Nikolaï, Anastasia decided to look for him. However she realized that unless she relied on the genetic memories of Shao Jun she would fail, and forced herself to synchronize with them, allowing her to use Shao Jun's skills.
After leaving her hiding place, Romanova noticed cannon fire as Red Army forces started marching into Kazan. As she continued through the city in search of Orelov, she freed three people she knew from before her ordeal that were being held prisoners by the Red forces. Entering a train station, Anastasia saw multitudes of refugees attempting to leave the city before the battle started proper as well as guards scanning the area. She proceeded while blending with the crowds in order to shield herself from the guards eyes and left through the station.
Outside the station, Anastasia overheard a conversation between two guards, one of whom claimed to have been just stationed at Bodarenko Ulitsa outpost, where they were holding Nikolaï, who hadn't told them the location of Anastasia and the Box. With this information, Anastasia was determined to help him escape. Romanova sneaked past the guards and boarded on top of a tram which she hopped would take her to the edge of the Volga, however the train was stopped for inspection forcing her to get off and find the signal box to change the light to green while avoiding being spotted by the patrol. Once done she quickly returned to the Tram before it left and continued riding it until it's final stop, where she climbed on top of the nearby buildings and jumped on top of a train headed near Trotsky's Mansion. Once the train was as close as it would get her Romanova jumped off and continued on foot, through some Cheka barracks, reaching the mansion where Orelov was held captive. Here she assassinated all of Orelov's captors and rescued him. Nikolaï, worried, asked her if she had been taken over by Shao Jun, but Anastasia reassured him that she was herself.
Once Anastasia rescued Nikolaï, he suggested that they split up in order to avoid detection from the Templars. Distressed, Romanova believed that Orelov wished to abandon her but he reassured her that he'd be covering her from the rooftops while she stayed on street level as they headed towards the Volga. On their way out of the compound, Anastasia sneaked through guards' patrols and through buildings while Nikolaï covered her with his rifle from afar. At times, Romanova lured troublesome guards near windows or open areas, allowing Orelov to shoot them. Soon enough Anastasia encountered a barricade which she could not pass through. However moved a barrel filled with explosives for Nikolaï to shoot destroying the barricade, allowing her to pass through.
Arriving at a warehouse near the docks filled with guards and explosives, Anastasia dropped explosive barrels near the main doors, allowing Nikolaï to them, killing the guards and clearing the way for her to get through the area. Once through Nikolaï once again covered Anastasia as she crossed a bridge, this time, however, an alert was raised and many guards converged on her location as she ran over the bridge. Once through she pushed another explosive barrel towards the bridge, allowing Nikolaï to blow it up.
Once clear of the guards, Romanova and Orelov took a small rowboat on the Volga. While drifting in the water Anastasia reminisced over her losses and Nikolaï reassured her of her ability to get through her current predicament. Anastasia resolved that she, as Anastasia Nikolaevna Romanova, could not continue to exist.
Arriving in Moscow, Anastasia and Nikolaï met Sergei, an Assassin scientist, who took the box. Anastasia asked him if he could cure her to which he clarified that while he couldn't, their Mentor might be able to. Sergei said he'd take her to him, but when Nikolaï prepared to accompany them, Sergei reminded him that he had to go to the Bureau to report all he had seen. At Nikolaï's protests, Sergei reassured him that Anastasia would be safe. Anastasia reassured him as well as she walked away with Sergei.
Unbeknownst to Nikolaï, Anastasia was taken by the Assassins to the Kremlin in order to experiment on her in an attempt to extract the genetic memories given to her by the box. While being brought there, Anastasia fought her captors, even having to resort to biting one of the Assassins that attempted to handle her, but was subdued. Once underground in the Assassin science facility, she was subjected to procedures that had previously resulted in subjects either being killed or permanently damaged.
Eventually Orelov arrived, having betrayed the Assassin's in order to save her. Upon being waked from unconsciousness, Anastasia noticed Nikolaï on the other side of an observation window as he remotely opened a door for her. Orelov apologised for his involvement in the situation and Romanova once again took the persona of Shao Jun — her psyche unstable due to the experiments performed on her — and launched in to a diatribe against him, threatening to kill him as "she" had the Tigers. Nikolaï called out to her in an attempt to ground her in herself, and urged her to run.
Once outside of the experiment room, Anastasia attempted to escape the Kremlin. While moving through the facility, she noticed two of the scientists that had experimented on her and Assassinated them for the cruelties they inflicted upon her. Romanova proceeded to the maintenance levels in her attempts to escape, dodging scalding steam sprouting from the decrepit machinery, eventually reaching a path blocked off by steam entirely and finding herself unable to keep going forward until Orelov activated a piece of machinery that blocked the steam enough for her to pass.
Once through the area, Anastasia attempted to open a security door which locked her into an airtight room with gas filtering in, choking her, only surviving through the quick intervention of Nikolaï, who stopped the gas and opened the door forward. However due to this, the pipes began to burst, starting a chain reaction that forced the weakened Anastasia to flee from the explosions behind her. Once outside Romanova once again reunited with Orelov. Their reunion was short lived however as a tank approached them to attack. Nikolaï ordered Anastasia to run towards the Bolshoi while he distracted it, once again promising to meet her later.
Having escaped successfully from the tank, Anastasia later met Nikolaï outside the Bolshoi theatre, having disabled the tank and escaped himself. Once together Anastasia asked Nikolaï how to leave the country. Nikolaï answered by giving her the fake papers that he had prepared for his wife, Anna, as he had been preparing to leave the country with his family. The papers where those of an "Anna Anderson", which, Anastasia commented, sounded American and would serve her even in Germany, where she was headed.
Anastasia thanked Nikolaï and bid him take care of his family and escape the country himself. Nikolaï expressed concern for her state of mind after what the Assassin scientists did to her and her being alone, but Anna replied that she had the strength to survive, despite not knowing if it came from Shao Jun or herself. Nikolaï questioned if she knew who she was, to which she simply replied that she was Anna Anderson.
Anastasia was 17 years old when her family was killed and was distraught when her she found out. However, a need to escape with her life as well as overhearing the callous and sadistic remarks made by Bolsheviks regarding her slain family imbued her with enough anger that she became willing to violently kill several men to escape, also taking cold satisfaction in punishing those who celebrated her family's deaths.
Anastasia was not adept at using weapons by age 17. Once imprinted with Shao Jun, she inherited many skills and abilities from the Chinese Assassin, including freerunning, lockpicking, and Eagle Vision, as well as the intrinsic knowledge of how to build Rope Darts - Shao Jun's signature weapon.
Unlike the Master Assassin Nikolaï Orelov with whom she travelled, Anastasia's equipment was limited to a knife given to her by Orelov and her makeshift rope darts, which she used with great skill.
- Historically, Anna Anderson was an impostor who insisted she was Anastasia Romanova; while her claims were never proven, they became notorious due to extensive media coverage. After the collapse of communism in the Soviet Union, the bodies of the Romanov family were subjected to DNA tests, revealing that the real Anastasia had died with the rest of her family on 17 July 1918.
- The premise of Anastasia surviving the execution of her family and serving as the main heroine of a story, was previously explored in both a 1956 movie and a 1997 animated movie both titled Anastasia, the latter of which was later made into a musical in 2016 that then got updated for Broadway the following year. Coincidentally, in both that story and in the Assassin's Creed one, Anastasia tries to get out of Saint Petersburg by train only to then have to get off it to escape those out to kill her (the Bolsheviks in the Assassin's Creed story and Broadway Musical, and Rasputin's demonic imps in the animated film).