It was finally over.
Twilight and her friends had finally defeated Tirek with the magic from the box, (Rainbow Power, as a certain pegasus wanted to call it), and sent him back to Tartarus where he belonged. She even got a castle out of it.
Now Twilight was in said castle, partying with all of Ponyville there to celebrate their victory.
As the party began winding down, Twilight made her way through the crowd, passing each of her friends on the way. Rainbow was recounting the tale in some surely exaggerated detail to a group of colts and fillies, with Scootaloo up front, drinking in every word. Pinkie Pie was, unsurprisingly, dancing wildly at the center of the party. Applejack and Spike were near the punch table speaking to some other ponies, with Rarity not too far off, lost in admiring the castle's beauty. And last was Fluttershy and Discord on the far side of the room to her left, laughing and talking together.
Normally Twilight would have joined any of them, but there was somepony she'd been wanting to talk to all evening. As she approached, she called out,
"Princess Celestia?"
The alicorn was standing in a quiet corner of the room, sipping punch and chatting with her sister, Princess Luna. They both stopped and looked her way upon hearing her voice.
"Greetings, Twilight Sparkle," said Luna. "Congratulations on your new castle."
"Oh, um, thank you," Twilight said nervously. It felt weird having her own castle, especially in such a simple town like Ponyville.
"Is something wrong, Twilight?" asked Celestia.
"Oh, no. I was just hoping to ask you a question," she answered.
"Of course; ask away."
"I'm sure you noticed me and the girls'... new looks from the Rainbow Power, right?" she began.
The Sun Princess chuckled. "Yes, it was quite hard to miss."
"Well, I was just wondering... why? Why would the magic need to give us makeovers in order to be used? I mean, I'm not really complaining but.... Giant hair, altered cutie marks, and random dye jobs? Doesn't that seem a bit... unnecessary?
"But then I realized I'd seen something like this before; the Crystal Heart. Whenever it's powered up, all ponies in the empire, crystal or not, get new mane and tail styles as well.
"So my main question is: is magic somehow.... tied to a pony's looks?"
Princess Luna, who had been taking a drink, spit her punch back into her cup as she and her sister stared nervously at the purple alicorn.
"Oh, what do you know? I do believe someone called me.... on the other side of the room! I'd best be going now!" And with that, Luna hurriedly trotted across the room.
Twilight frowned at the strange behavior. "What was that about?" she asked the remaining princess.
Celestia sighed. "I suppose it was only a matter of time before you found out," she began.
"Found out what?"
"You were half right; magic is tied not to a pony's overall look, but rather, one thing." She leaned in close and whispered, "Their hair."
"Wait, seriously? It actually is?" Twilight asked, shocked. "I thought that was just my mind coming up with something ridiculous due to this exhausting day!"
'Well, ponyfeathers,' Celestia thought. 'I should've just let her think that.'
"And why the hair? That doesn't make sense, unless... oh! I get it. You're joking, right?"
'Might as well just tell her...' "We can't talk here; there's too many ponies." She motioned for Twilight to follow her. Quietly sneaking out the doors, they entered one of the many hallways. They walked in silence, the only noise the sound of hooves on the cold, hard floor.
Finally they came to another door, leading to the throne room. Only once they had entered and Celestia safely shut the door did she turn to Twilight and speak again.
"This is no joke, I assure you."
"But.... what does hair have to do with anything?" Twilight asked, confused.
The Sun Princess smiled. "Have you never wondered why my and Luna's hair flows like this?"
"Well... I always figured it had something to do with you being the most powerful ponies in Equestria... Wait, you're not saying.... your power comes from your hair?!"
"And surely you've noticed many powerful ponies in history all have something in common with their titles? Starswirl the Bearded? Morari the Maneless?" Celestia continued.
"I just thought that was because he had an incredibly huge beard!"
"That he did; that was his secret. The magical powers stored within his beard allowed him to become one of the most powerful unicorns in Equestrian history."
"You've got to be kidding me." Twilight stared at her mentor, looking for any signs of teasing; there were none. Either she was serious, or very good at hiding emotions.
"Morari is a different case," the white alicorn went on. "He had fine, powerful hair; at least until his tragic accident."
"Accident?" Twilight echoed. She didn't remember reading anything about that.
"Yes, he foolishly tried to face a dragon on his own; a very cranky, fire breathing dragon. Almost burnt him to a crisp."
"The dragon set him on FIRE?!" Twilight gasped.
"Oh no, he put up a protection shield just in time. The next day he woke up, took a shower, and lost every single hair in his mane and tail. Turns out somepony snuck hair remover in his shampoo. After that, his magic was severely weakened. He spent the rest of his life writing books on magic instead. I felt so bad for him, I made sure there was no mention of it in the records.
"He never did find out who exactly was behind it. Some said it was Chancellor Puddinghead the third, playing a prank. Others think it was another unicorn trying to eliminate the competition. Oh, and you'll love this one. A couple even said it was the dragon, trying to get revenge." Celestia let out a rather un-princess-like snort. "Like nopony's going to notice a giant dragon lurking around? Not to mention his enormous claws could never manage to grasp that little bottle, anyway."
"No offense, Princess, but I'm still having trouble believing this."
"Understandable." Celestia nodded. "But it's happened with you and your friends several times, besides the ones you mentioned.
"For instance, I seem to recall you telling me when you and your friends were searching for the Elements of Harmony, you met a sea serpent crying over his moustache, which Rarity then repaired by chopping off her own tail. Later on, however, after your first use of the Elements, they restored it."
"I'd forgotten about that," Twilight admitted.
"Another example is when you told me of Pinkie Pie's mysterious 'Pinkie Sense,' involving, among other things, a twitchy tail.
"And last but not least, I'm sure you remember the events of the day you were visited by yourself; which was also the day Cerberus left the gates of Tartarus, and Tirek escaped?"
"Of course," Twilight replied. She laughed. "I still remember how ridiculous I looked; running around in that silly spy suit, eyepatch, and head bandage, not to mention that awful... mane style..." she trailed off, eyes widening, as she looked up at her mentor. "Are you saying...?"
"I'm afraid so." She nodded grimly. "Luna and I believe the sheer awfulness of your mane that day triggered Tirek's escape.
"You see, bad hair can affect magic just as much as good hair; only it tends to strengthen dark magic. So, an Element Bearer having a dangerous haircut caused a shift in the magical balance in the world. How did you think such a severely weakened centaur locked in a cell in the depths of Tartarus managed to get out? The fact Cerberus left his post wouldn't be his only problem."
"But, wait; Spike didn't burn my hair until after that!" Twilight exclaimed.
"Technically, no; but it had happened to your future self when she came to visit you. In other words, even though the incident hadn't happened yet, the moment 'Future Twilight' entered our present time, that haircut existed."
"I... I don't believe it," Twilight muttered. "All this time... why didn't you tell me sooner?" 'Please don't say "Because you didn't ask,"' she thought.
"This is very delicate information; I just didn't want it falling into the wrong hooves. Not that I don't trust you to keep it secret," she quickly added. "But I figured the less ponies that knew, the better."
"Of course... I understand. I won't say a word," the younger alicorn promised.
Celestia nodded in approval. "Good. Now, why don't we head back to your party? It won't do to not have the guest of honor there." She smiled.
"Right..." Twilight agreed, though it seemed she was only half paying attention. She slowly exited the room, her mind more focused on what she'd just learned.
The Princess of the Day hung back a moment, proudly admiring her once-student's new throne. She turned when she heard the door open again as her sister entered.
"Did you tell her?" Luna asked.
"Yes, I did."
Luna raised an eyebrow in suspicion. "All of it?"
"Of course. Why wouldn't I?" Celestia asked.
Her sister began to circle her as she asked, "And was all you told her the truth?"
The elder alicorn scoffed, insulted. "Just what are you trying to say? Of course I told her the truth!"
The Night Princess stopped in front of her. "Nothing," she stated. "But we know how much you love to... what was it again? Ah yes, troll."
"Well I assure you I was not," Celestia said. She glanced at the door Twilight had exited out of the corner of her eye, and said with a small smirk, "Not today, anyway."
Author's Note
I apologize for any facehooving that may have taken place when reading this story. 
This was just a silly idea that popped in my head, don't take it too seriously.
But I thought, 'A lot of times really important magic events happen, the hair always seems to be affected somehow.' Besides the ones mentioned in the story, there's also when all the ponies in Starlight's town got their cutie marks back; they also got their old hairstyles back. And then Starlight herself got a new hairdo after her reformation. http://lparchive.org/Dominions-3-(by-Lilli-et-al)/Update%20168/59-WxNy9.gif
I know most people will say 'Because Hasbro wants to sell toys' and that could be it. Or maybe that's what they want you to think 
Might add a second chapter with more on this and the villain hair if people want.
Thanks for reading!
