(PROSE: Engines of War C3) AC

'Eradicate!' burred the Dalek with the cannon, rotating its mid-section to track him as he ran.
'Finch!' cried Cinder. 'No!'
The cannon fired, emitting a pulse of eerie, ruby-coloured light. It struck Finch in the back and seemed to engulf him entirely, encircling his body, whispering around him as if looking for a way in.
He stopped running, twisting around in obvious agony and thrashing as if trying to free himself of the beam's deadly embrace. There was no escape.
He opened his mouth to scream, and the stream of light rushed in through the orifice, pouring into his body, choking him. He clutched at his throat with both hands, scrabbling for breath.
As she watched, tears pricking her eyes, Finch's flesh began to glow, taking on the same odd, pinkish hue as the light. He seemed to disintegrate before her, fading out of existence, as if the light inside of him was pushing out and expanding, dissolving him from within.
In less than a few seconds, there was nothing left of him whatsoever, aside from a faint wisp of slowly fading light.
Crouching behind the burned-out Dalek, Cinder felt an odd sensation. She knew she'd just witnessed something horrific, but, for some reason, she couldn't quite understand what. Her memory seemed suddenly fuzzy, confused.
She had the unsettling notion there was something she couldn't remember, scratching away at the back of her mind. She could have sworn the Degradations had just exterminated someone, maybe even someone she knew, but she couldn't imagine who it could have been. After all, she'd planned this ambush alone, with no help. Hadn't she?
Nevertheless, she couldn't deny the overwhelming feeling of hollowness, as if she was experiencing the absence of an emotion akin to grief.

[...]

The Time Lord gave her an approving look. 'An ambush?' he echoed. 'Just you, your friend and a single, salvaged Dalek energy weapon. I'm impressed.' He looked momentarily forlorn. 'I'm sorry I couldn't save him.'
Cinder looked at him, confused. 'My friend? I was alone.'
The Time Lord frowned. 'The TARDIS picked up two human life signs in the crash zone. One of them disappeared just after a massive energy discharge from one of the Daleks. I'd assumed you were together.'
Again, that strange itch at the back of her mind, as if there was something she should be able to remember, but couldn't. 'I...' She hesitated. 'I don't think so,' she said.

—Chapter 3

[...]

'But why didn't you take anyone with you? You know the rules. It's not safe to go out there alone.'
'I wasn't alone,' she replied. 'I had John Smith here, didn't I?'

[...]

'Tell me, whose is that bunk over there, beside yours?'
Cinder glanced at the other makeshift cot, only a metre or two from her own. It seemed oddly familiar. 'I don't...' She hesitated. 'I feel as if I should know, but I don't,' she said. 'It's the strangest feeling. Like something' missing.'

—Chapter 5

[...]

'It's the weapon, Cinder. That's what's doing it,' said the Doctor. 'That cannon—it can erase a person's timeline from history, removing every trace of them, as if they never even existed. It's what happened to your friend, out there in the ruins, the person whose bunk was next to your own at the camp, the one you can't quite remember. Your mind is struggling to comprehend it. You know there's something wrong, something missing. The memories are still there, buried inside your head, but they no longer add up, they no longer relate to a person you've known and seen, because reality has warped around you.'
Cinder shook her head, as if trying to clear it. She didn't understand. A weapon that not only killed someone, but rewrote history as if they'd never even been born? It was the most awful thing she'd ever heard. The sheer violence of it—to not only take a life, but to undo every action, every thought, every emotion ever enacted or experienced by that person... it had to be the most evil device ever conceived. She wiped tears from her eyes, remembering the grief, if not the people.

—Chapter 6