Author's note, updated May 30, 2015: This story is far from over. It has been on an extended hiatus, from which it is about to return. However, due to semantics and overall incompatibility of the current chapters to the overall story, the entire story will be rewritten shortly. I apologize for any inconvenience this may cause, and hope that I do not seriously inconvenience any of my readers.
Twilight groaned as she awoke. Above her, light streamed in from a large hole in the ceiling of the cavernous expanse she now found herself in.
"I must have fallen in..." Twilight mused aloud.
Beside her, Twilight heard a soft sound, like a whimper. She turned her head to find Rainbow Dash lying upside down against the wall. Her eyes were clenched shut, and Twilight judged she was in serious pain.
"Are you alright, Rainbow Dash?" She asked, not hiding her concern.
The cyan pegasus weakly opened one eye and looked at Twilight, then attempted to nod. In the act of doing so, however, she tilted her body mass and was rewarded by a resounding flop into the rocky floor of the cavern. Twilight was by her side in the same second.
"Are you ok? Are you hurt?" Twilight asked as she lifted the mare's face off of the ground.
Rainbow Dash looked at Twilight with an expression of utter defeat. She opened her mouth and pointed to it.
"You can't talk?" Twilight asked, guessing at Rainbow's intended meaning.
Rainbow nodded, then pointed to her right wing. Twilight hadn't noticed, but it was stained a bright crimson and bent at an awkward angle. There were also some white structures penetrating it at various points. Twilight gingerly touched it with her hoof, causing Rainbow to jerk away.
"That needs to be taken care of right now," Twilight said as she attempted to use a basic healing spell.
But instead of casting a spell, Twilight felt an intense pain in her forehead. She staggered backwards and placed a hoof on her forehead. It was hot to the touch, like embers from an open fire. She quickly stopped her spell and brought her hoof to her horn. It hurt to the touch, sending a sharp pain all the way down her spine.
"My horn's swollen," she said quietly, "Probably broken from the fall. I can't use any magic."
Rainbow nodded grimly, then grimaced as another pulse of pain shot through her wing. Twilight quickly searched the immediate area, and picked up a branch and a small section of vine that had fallen in with them. She then placed the branch parallel to Rainbow's broken wing, did her best to realign the bone (causing the bruised pegasus to bite her lip in pain), and tied the branch and wing together using the vine segment.
"Is that better?" Twilight asked eagerly.
Rainbow slowly nodded, then gave her wing a few short, slow flaps. The makeshift cast held, and Rainbow gave a weak smile, which was quickly replied by Twilight. She then looked around the cavern with an inquisitive expression on her face.
"We need to find out where we are," Twilight said as she looked up at the hole, "And how to get out of here."
Rainbow nodded and started walking. Twilight quickly joined her.
• • •
"'If you're tryin' ta find me,'" Applejack read with an irritated voice, "Ah've gone ta Canterlot for official royal duties. Ah will be back before 3:00 PM on Tuesday. ~Twilight Sparkle.' Well, it's 4:30 on Wednesday and she still ain't here. Where in tarnation do ya reckon she is?"
"Oh, dear," Fluttershy responded timidly, beginning to pace, "What if she's in danger? Or trapped and scared and hungry with no way to get out? Oh, poor Twilight!"
"Fluttershy, dear," Rarity said, putting a hoof on the yellow pegasus's shoulder to calm her down, "I'm quite sure she can take care of herself. She's probably still at Canterlot. Something probably came up that required her attention. Royal duties can be quite cumbersome."
"And I s'pose you'd know about royal duties," Applejack said in a deadpan voice, earning an annoyed look from Rarity.
"I never claimed to, Applejack," she replied matter-of-factly, "But it's not a preposterous idea. Certainly more likely than Twilight avoiding-"
Rarity was interrupted by the sudden appearance of Pinkie Pie, whose face was an expression of pure worry.
"I just went over to Dashie's house to ask her if she wanted to come to the pond with me, so I went over to her house and used my flying bike, because everypony knows an earth pony can't walk on a cloud like a pegasus can, so I used my flying bike to get to her house, and I went to her door and knocked, and knocked, and knocked again, but she never answered! So do any of you know where Dashie is so I can ask her-"
Applejack put her hoof in Pinkie's mouth to silence her.
"Whoah there, Nelly," she said as she removed her hoof from the other mare's mouth, "Start over again, and this time talk a bit slower."
"Rainbow Dash is gone!" Pinkie cried dramatically, regaining her composure a moment later, "Have any of you seen her?"
"So Twilight and Rainbow Dash go missin' at the same time," Applejack mused, "Somehow Ah don't think that's a coincidence."
"I agree," replied Rarity, "But why would Rainbow Dash go to Canterlot?"
"Ah wonder what those two're doin'," Applejack said, essentially ignoring Rarity, "And why didn't they tell us?"
"Where's Twilight?" Pinkie asked, suddenly noticing the absence of the new princess.
Applejack and Rarity both rolled their eyes.
• • •
The cavern became increasingly dark as Twilight and Rainbow continued walking, but Twilight still noticed that Rainbow was walking with an uneven gait. It appeared she was limping, and it became more noticeable with every step she took. Twilight was about to ask her about it when the rainbow-maned pegasus suddenly fell forward.
"Are you ok Rainbow," Twilight asked, growing more concerned every minute they are stuck in the cavern, "What happened?"
Rainbow attempted to stand back up, but her left foreleg buckled as soon as she put weight on it. Twilight quickly examined it.
"It's broken," she said, her voice lined with incredulity, "What did you do to injure yourself so badly?"
Rainbow wouldn't look her in the eyes, so Twilight let her question go unanswered as she hoisted the crippled pegasus onto her back.
Progress was slower, now. Much slower. Twilight could only walk a fraction of her previous pace, and had to stop frequently to rest (she hadn't carried this much weight without magic since she attempted to restock the library in Canterlot as a filly, and even then she couldn't handle it well. She wasn't allowed in the library for a week after that).
Twilight couldn't help but notice the irony of their situation. Here were two mares, both of whom could fly, trapped in a cavern from which they needed only to fly to escape. As she thought about this, though, realization came to her that her wings weren't broken. But it didn't matter now. Not only were they too far from the hole now to try and relocate it, but Twilight could only barely fly alone, much less while carrying another mare. And there was no way she would leave Rainbow here alone.
Rainbow's head rubbed against Twilight's mane. She had fallen asleep. Good, thought Twilight, She needed that. She then gingerly lay Rainbow down next to the wall, and lay down herself. She thought then of another irony. Here was Rainbow Dash, a symbol of independence, loyalty, and strength; here was a mare who could not fly, walk, or even speak. She was completely dependent.
...On me, Twilight added in her thoughts, She is completely dependent on me.
This thought struck Twilight like a brick. Responsibility had always been expected of her as Celestia's student, Spike's caretaker, and recently as a princess of Equestria. But never had anypony been so absolutely dependent on her as Rainbow Dash was right now, except maybe Spike in his infant years. Here one of Twilight's best friends, the holder of the Element of Loyalty and a symbol of strength and independence, could not even walk. It was a sad thought, and one that made Twilight even more protective of the cyan mare. As she lay down beside her, a thought formed in her mind. One that stayed with her as she drifted into sleep.
I won't let anything happen to you.