"Again." Salem commanded, her eyes turned skyward.

When Ambrose had brought Slate Blanc back to her Palace, the man had quickly revealed his information. A plan had quickly been made, and she had left Ambrose and Slate behind, taking her Little Courtier with her.

Petra Nullus' first mission for her Queen.

It was considered a bad idea to have one's aura and semblance activated in childhood. The side effects were well-documented. Salem would know, she'd run many an experiment to investigate the matter on the children of those courtiers that had disgraced their lines (some children had even volunteered in a bid to redeem their families.).
Life Expectancy was lowered by almost a third, as was the amount of aura one could potentially have at peak. Mental instability was common, as was loss of taste, and stunted growth among other side effects.

But the possible upsides..?

A stronger, less random semblance (to the point that it could practically be induced), A stronger aura to make up for the lessened amount. A heightened awareness of one's surroundings. A need for less food, drink and sleep (along with increased alcohol tolerance, for reasons Salem preferred to leave a mystery.).

So it was with some degree of regret that she went ahead, and had Ambrose activate Petra's aura. The man had taken to his task with an almost sadistic glee, smiling as the child screamed and cried and begged for mercy as her soul was forcibly made manifest.
Salem had let the girl sleep in her bed with her that night. It was not a restful night for the young girl, spent curled up against Salem's side and trying not to whimper.
Whilst the sight had pulled at whatever was left of the Mother she once was, the God-Queen of the Grimm was of the belief that the pain would be worth it in the end. It would provide a solid base for the Nullus line should this 'round' of her conflict go on for another generation or three.

And then, there was her semblance…

So here they were, standing in a valley in the Northern Mistralli Mountains in the early hours of the morning. According to both Ambrose and Slate, they were directly beneath the flightpath of the prisoner transport vessel. Within it was someone with the potential to be her next Left Hand.

She was perfectly capable of ripping the ship from the sky herself, and would indeed do so if Petra failed. But she was adamant that Petra Nullus be given a chance not to begin her service to her with failure, but with triumph.

"I can't!" Her Little Courtier protested, arms held tightly across her chest. "It's too far!"

"You will find that with practice, nothing is out of your reach." Salem advised as she moved to rest a hand upon the child's shoulder. "Harden your resolve Little Courtier, harden your desire.Visualise it. And pull that ship from the sky."

The child took a deep breath and raised her arms. She squeezed her fingers, and bit her lip. Nothing.

Again.

And again.

And again.

Her face grew red, and her eyes watered at the strain. Petra let out an agonised scream, one that went on for far longer than a child's throat should be able to manage…

…a scream that was soon drowned out by a metallic groan that could only come from a vessel falling to Remnant. She hadn't managed the whole ship, but one engine was all it needed to take.

"..Exceptional." Salem clapped her hands in approval. "Truly exceptional. You have done superbly, Petra"

Her Little Courtier didn't respond, she merely slumped face first to the ground. Utterly exhausted.

The potential for the modern world to betray itself. For buildings and cities to literally be torn down.
The potential for weapons to betray their masters.

Domination over one of the fundamental elements that governed Remnant itself.

Control over magnetism