She did not like hurting people. Her personality changed with the more people she absorbed and the more memories she had access to. Aspects of those absorbed would leak into her outlook and goals.
Matryoshka is described as having a great many vertical and horizontal lines to her form, with dark horizontal lines ribbing her entire body. This is largely when her powers were active however, as she is able to largely "pass" as human.
Matryoshka can turn herself into a mess of ribbons, when inactive she has a humanoid form with horizontal lines across her body. When absorbing an individual, some of their memories and appearance are absorbed into her costing some of her own. This effect can be repeated, but holding on to anyone too long ‘digests’ them. This can lead to the obfuscation of her personality as more memories and experiences are added to her own, shifting her.
She showcased the ability to hold people in suspension without absorbing them. As this was post-Gold Morning it is unknown if she always had this ability or it was a recent development.
She linked up with two other Case 53s, Gwerrus and Egesa, and they held some civilians hostage. Gwerrus tried to convince her to subsume a hostage so that they'd have an easier time in the world but Matryoshka demurred due to what the process would do to her.
They were attacked by a group of heroes engaged in fighting an endbringer. Gwerrus was likely killed by one, and Egesa was driven off. It is not known if was not seen later. Matryoshka would be trapped in the city when Madison was quarantined. She did not appreciate this migration.
She meets Faultline’s Crew there having spent 2 years within the walls of the quarantine zone. She had fallen in with a group of survivors, able to pass as human thanks to continued use of her abilities and camouflage body paint. However Gregor was able to tell who she was.
↑ 1.01.11.2Civilians. Five of them. They were wielding improvised weapons. A makeshift bow and arrow, spears. Nothing that posed a serious threat to Newter.
“Why do you want to talk to the monsters?” the woman with the bow asked. She had improvised urban camouflage paint over her face.
“You’re on their side?” a man with a spear asked.
“Yes,” Faultline said. “But I could be on yours too.”
The woman with the bow stepped away from her comrades. Her weapon pointed in their general direction. “You have a way out?”
“And you just let us go? There’s no catch?”
“I… how do I know I can trust you?”
“You are one of us,” Gregor said.
The woman froze.
“Maddie?” a man asked.
“How did you know?” Maddie asked.
“I know this feeling, of being lost. Of being very alone and not knowing who can be trusted,” Gregor said. - Excerpt from Interlude 18.f
↑ 2.02.1Matryoshka – A monster with hair and body etched in horizontal lines, can unfold herself into ribbons and consume others, taking on a share of their memories and traits, simultaneously diluting herself. - Cast (Spoiler Free)
↑ 3.03.1Maddie? Matryoshka Absorbs others, gaining memories/traits at the cost of her own. Could layer, diluting her form with multiple consumed. Slowly digested eaten. Case 53 Independent - Parahuman List, bolded edit by Wildbow.
↑“Mirzuty,” the large woman swore. “Egesa say you take her, Matryoshka.”
↑Rounding out the group was a young woman. Something was off about her, besides the obvious physical changes. Thick black horizontal lines striped her body, crossing her eyes like a blindfold, extending from the corners of her mouth, lining her chin and tracing down her neck. By the time they reached her fingers, her skin was more black than white. She wore the same prison grays, but had donned a jacket and boots. Her blond hair was straight, her bangs cut severely across her forehead.
She was off because there was a rigidity to her. She stood too straight, and every part of her except her clothing seemed to be drawn in horizontal and vertical lines.
Scythe-arms finished laughing, took a second to compose himself, and then snarled with a viciousness that seemed to be in stark contrast to his previous humor, “Ontige hie, Matryoshka.” - Excerpt from Migration 17.4
↑Matryoshka had severe bangs, and was striped, strictly in horizontal stripes that changed her skin color as they extended down her face and emerged from her sleeves. - Excerpt from Infrared 19.a
↑“I used to have nightmares,” Matryoshka said, as the group started moving toward the doors. She had a heavy accent that sounded Russian. “I saw movies where aliens were caught and experimented on. I imagined being one of them. Strapped to a table, autopsied.” - Excerpt from Infrared 19.a
↑ 9.09.1She walked away from the group and across the room. As she did, her body started to come apart in ribbons. As the ribbons came away, they revealed someone beneath.
The ribbons came together, forming a complete, different person, and then opened up once more. Another person beneath.
So it went. Each layer was something of a close relation with the one before it. By the time she was on her fourth layer down, the first woman had recovered enough to get up and walk away.
The fourth layer down, as it happened, was Tattletale. Two of her bodyguards seized her before her weight could come to rest on the legs that still had bloody bandages on them. She was moved to a chair, and made a face as she sat down.
↑They entered the hotel room much the way they’d left, with a makeshift ladder leading to the balcony, and quickly settled in. Matryoshka gorged herself on the groceries Faultline had bought shortly after they’d arrived. She stared wide-eyed at the television. It was the first time she’d ever seen one. It led to her excitedly describing her world between mouthfuls of food. - Excerpt from Interlude 18.f
“I don’t know. But by the time I saw the chance to escape, I had to roll twelve dice and each one had to come up with a six. And if it didn’t, if I got more than a few wrong, they found ways to punish me.”
Gregor put his hands on Shamrock’s shoulders.
“They made me use my power. I… I think I was one of the people they used to punish the ones who failed their tests,” Maddie said.
“Christ,” one of the men said. “And the freak has been with us for a week?”
Maddie turned to glare at him.
“If it means anything,” Shamrock said, “I forgive you. You didn’t decide to punish anyone. We did what they made us do.”
Maddie flinched as though she’d been struck.
“Come with us,” Faultline said. “You don’t have to stay with us, but we want to hear what you have to say.” - Excerpt from Interlude 18.f
↑Matryoshka – A case 53, Matryoshka was deposited in Madison, Wisconsin by the same incident that drew the Travelers there. Described as having a great many vertical and horizontal lines to her form, with dark horizontal lines ribbing her entire body, she can turn herself into a mess of ribbons, absorbing an individual, some of their memories and some of their appearance, at the cost of her own. This effect can be repeated, but holding on to anyone too long ‘digests’ them. - Cast (In Depth)
↑Your thoughts & feelings on the various pieces are very much in line with my own. The parts I enjoyed writing were the parts you enjoyed reading. The parts you had quibbles, are the parts where I had doubts in the writing process.
I, too, had doubts about how Weld accepted her, but I told myself that he’s an accepting, trusting guy. He was ok with Skitter from his first appearance, and was respectful when crossing paths with her in the s9 arc. He’s just been hit by a major crisis of faith and a lot of major info, and he’s fallen into a leadership role with the other Cauldron-made. So, I told myself, it sort of makes sense that he’d be eager to accept more into the fold.
But… yeah. That doesn’t change that they should be more suspicious as a group.
So there’s significant issues in terms of the conception (Witness being created; it does make sense in-story, it was just poorly explained in two offscreen moments), and in terms of the conclusion (the acceptance of the character) with a handful of issues in between (One of my big problems with the chapter was that Vista was a prop).
And to top it off, yeah, Witness isn’t an essential character. She’s someone I might build an entire arc around, and if I wasn’t working steadily towards a conclusion, it’d make sense to introduce a complication like her. But there’s no need for her in the grand scheme of it. I’d intended for her to link Weld’s group to the narrative, but it’s not worth the added complication and the (severe) hit to the story’s tone.
So I think it’s just better to scrap it and cover the necessary bases in other ways. I wrote the chapter with too little time and too many distractions (flooring people stomping through and asking questions), and in retrospect, I shouldn’t have uploaded it with the doubts I had. - comment by Wildbow on the Missing Interlude
↑“Matryoshka, get the ones from inside,” Weld said. “Think you can manage?”
A young case fifty-three with horizontal lines marking the length of her body nodded. She began dissolving into ribbons as she made her way across the platform. - Excerpt from Extinction 27.5