It had been a single moment. The span between one heartbeat and the next. Mimic had come to understand what was about to happen, and she’d chosen to do nothing.
She’d changed her mind immediately. She’d saved his life. It had only been a moment.
She was a changeling, not a weak pony. She didn’t care about others. She cared about herself. A single moment was nothing.
She’d never pretended to be better. She’d never hidden the fact that she was watching out for herself first. What did one moment matter?
The excuses meant nothing to her. It didn’t matter why, or how long. Even if it had just been a moment, she’d been willing to do nothing. To let somepony... To let Thistleroot... The first pony, no, the first creature that had ever risked his life to save hers.
“I’m sorry,” Mimic said again, not moving, not daring to open her eyes.
Thistleroot shifted underneath her, nudging her head. She finally drew back, letting him sit up. He glanced back, spotted the fragment of harmony, and levitated it toward them. After a quick glance to be sure it wasn’t harmed he dropped it into his lap. “Okay, apology accepted. Why are you apologizing?”
Mimic didn’t say anything. She couldn’t bring herself to look at him. Just the thought of it turned her stomach. For just a moment, she’d been willing to do nothing. To let her friend...
“Mimic? What’s wrong?”
She had to lie. He couldn’t know what had been about to happen. It didn’t even matter that she was a terrible liar. It was Thistleroot. He’d believed her unwaveringly up to this point.
“Equestria to Mimic? Come in, Mimic?”
She just had to tell him that she didn’t think it would work. That she’d been wrong before. That the prison seemed too strong, now that she was close.
“Okay, well, while you’re spacing out, I’ll just be over here, uh, saving the world, I guess.” Thistleroot lifted the fragment of harmony once again.
“No!”
He flinched and then looked at her. “Uh, okay. Why not?”
“You just... can’t you feel that?” Mimic asked. “Can’t you feel all that energy running around up here?”
Thistleroot arched an eyebrow and then closed his eyes. His horn glowed softly. “Uh, yeah, now that you mention it. Makes sense with an enchantment this powerful. What’s your point?”
“So what do you think will happen if you go sticking your magic into that mess? That’s not a key your holding. If you use it to try to pick the lock...” She trailed off.
“I could end up bridging my own magic to the prison’s,” Thistleroot said, catching on. “Oh Celestia, I could have... oh, wow. That would not have been pretty.”
Mimic cringed, waiting for Thistleroot to catch up, to fully understand.
His face fell. “If that’s the case... I should have known.” Mimic steadied herself as his voice took on a sharp edge. “Rosalia tried to kill me.” Mimic blinked. “I knew she wasn’t playing on the level, and I still almost walked right into it.” Thistleroot shook his head and tucked the fragment of harmony back into his pack.
“Huh?” Mimic asked.
“I should have known she wouldn’t be that honest about it.” He made his voice high pitched in a terrible imitation of Queen Rosalia’s voice. “Here, take this dangerous weapon, because when you come back to fight us with it, I’ll just kill you.” Thistleroot closed his eyes and started toward the ramp. “I mean, obviously I would start looking for other ways to use the crystal. So as soon as somepony suggested...” He paused, his steps faltered. A moment later, he shook his head and turned back to her. “Thanks, by the way.”
“Thanks?” Mimic asked. Had she heard that right?
“Yeah. If you hadn’t noticed what was about to happen, well...” Thistleroot rubbed the back of his neck. “I guess my next Nightmare Night costume would be the headless horse.”
Mimic tried to accept the thanks, to tell him that it was fine. She wanted to joke, to tell him that they were even for Canterlot Tower. The shame twisted in her chest again and she stayed silent.
She could see in his eyes that he wanted the same thing. He understood, but he wanted to be wrong. He wanted her to accept the praise. He wanted her to take a jab at him for being careless. She didn’t. She watched the warmth leave his expression each second she stood silenced by guilt. She watched him drop his hoof, his posture going from carefree to guarded.
She watched her friendship die.
“Mimc,” Thistleroot said, “why did you say you were sorry?”
She couldn’t bring herself to lie, and she didn’t dare tell the truth.
Her silence seemed to be answer enough. “You’re the one who suggested we use the fragment to free the princesses,” Thistleroot said. “Rosalia even said she talked to you before I woke up.”
“I stopped you,” Mimic said. It was the only truth she could cling to.
“Did you know? Before we got here, did you know what could happen?”
“I-I thought... I knew it was possible.”
Thistleroot closed his eyes long enough for a single, deep breath. Silence fell between them. Finally, he asked, “Why?”
“I didn’t know for sure,” Mimic said. “Not until we got here and I could feel it for myself. I didn’t want to hurt anypony, so Rosalia told me that I needed to get rid of the fragment of harmony. She told me that you’d agree to use it here, and then it would be wasted. Then no one would have any reason to go after her or Nocturne.”
“Why didn’t you tell me sooner?” Thistleroot asked.
“She threatened—”
“I know she threatened you!” Thistleroot shouted. Mimic winced and took an involuntary step back. “She threatened all of us! I’m not asking why you agreed to do what she asked. I’m asking why you didn’t tell me sooner? Why didn’t you tell me while we were walking back to Canterlot?”
“I wasn’t sure that this would be dangerous. I didn’t even think you’d be able to use the fragment.”
“So, best case scenario, you were just wasting my time while the others are out there? Worst case, you were trying to get me killed, and then the nice middle of the road is the one where you convince me to waste the only tool we have left because Rosalia told you to? Does that about cover it?”
Mimic tried to answer, but faltered.
“That’s what I thought,” Thistleroot said. “You didn’t say anything when we first got up here. You didn’t say anything when the fragment started working. You waited until the last possible second.”
Mimic looked down, unable to meet his gaze any longer.
A long time passed before Thistleroot spoke again. When he did, his voice was softer, no longer filled with heat. “You hadn’t decided yet.”
The sound of his voice, faint, disbelieving and broken, filled her with a fresh wave of guilt. She blinked back tears that threatened to well up. “I’m sorry.”
There was no response. When she looked back up, Thistleroot had left. She didn’t follow.
Rosalia had told her what would happen. There will come a day when you find yourself hated and alone. The changeling queen had been wrong about one thing, though. Thistleroot had been her friend.
She remembered Rosalia’s other warning as well. Words that she hadn’t understood at the time. Or maybe she just didn’t want to understand. Love is a mistake that will create for you no end of grief.
Mimic considered leaving, but realized she had no place to go any more. Finally, she lay down where she stood, resting her head against her front legs.
“I’m sorry,” she said one last time.
There was no answer.
*****
Thistleroot wanted to be angry. He had been angry at first, before he realized exactly what had happened and it had slipped through his hooves. Anger was a fire. It was hot and alive, and there was no room for it beside the ice that had flooded his chest.
Mimic had lied to him. Mimic had led him to Canterlot Mountain, and nearly let him get killed. It was hardly a consolation that she’d stopped him at the last second.
He could be mad at her for wasting his time. He could be mad at her for trying to get him to waste the fragment of harmony. But she’d done more than that. There had been at least a part of her ready to watch him die.
The walk down the ramps built onto Canterlot mountain dragged on.
Had he thought they were friends?
He had. How could they not be friends, after everything that had happened? Canterlot Tower and Libiris and Night’s End. Apparently Mimic thought differently.
And there was the anger again.
Thistleroot didn’t know what to do with it. It had been so long since he’d been angry. Truly, painfully angry.
He wished his magic was stronger, like Twilight Sparkle’s or Spell Shine’s. He wanted to be able to shoot beams, to smash things, to break things, if only to vent his anger. Instead he just kept moving. Across and down. Turn around. Across and down. Turn around.
How had he been so stupid? How had he ever considered her a friend? She had only accompanied them because she thought it was her best way to keep herself and her brother safe.
Her brother. The changeling that had taken Thistleroot’s place. The changeling that had tried to kill Scootaloo. Just knowing that should have been enough of a hint. Thistleroot should have realized. But he’d been too stupid.
The last ramp ended and Thistleroot stepped back onto the streets of Canterlot. Back onto what had once been his home, before Nocturne had destroyed it. Nocturne and Rosalia and the changelings. And Mimic.
He walked North, toward the Canterlot refugee camp, toward those ponies that had chosen to stay and begin rebuilding.
He passed the street where his favorite donut shop had been. The place he and Scootaloo had visited after their first run in with the crusaders. The place he’d first met Mimic during the Battle of Canterlot.
He passed the Canterlot Gardens, where he’d watched Mimic kill a pony.
Not far past that, he passed the fallen Canterlot Tower, where he’d saved her life from the fall, and she’d saved his from Star Shine.
He’d stopped walking and dropped into a sitting position, though he wasn’t sure when that had happened. He grabbed a chunk of stone and threw it against the ground. It bounced, one corner fracturing. The destructive impulse was far less satisfying than he’d hoped. He tried again with a larger piece, but was met with the same feeling of futility.
His anger faded as he watched the stones he threw bounce harmlessly against the street. Once it was gone, he was left feeling empty. Alone, surrounded by the remains of his ruined home, he couldn’t hold himself together any longer. His chest heaved, a single sob escaping. He felt a cold wetness run down his cheeks. Once that first tear fell, the others followed. He sat amongst the rubble, not even trying to stop them.