"You want me to what?" Twilight asked.
"I just need you to change the color of one teensy-little bit of hair," Rainbow explained in the middle of Twilight Sparkle's foyer.
"What's wrong with your hair?"
"There's just one of them that... isn't the right color," Rainbow Dash said, looking down at the floor and hoofing the rug.
Twilight raised an eyebrow and grinned as she looked at the pegasus' mane. "Your mane's a rainbow, Rainbow Dash. It's supposed to contain every color of... well, the rainbow. And gray is a color," she giggled.
Rainbow Dash pouted. "Well, I've never seen a rainbow with gray in it. And I've made quite a few of them. In case you forgot."
Twilight smiled. "Gray hair is just a natural part of life Rainbow Dash. There's nothing wrong with it," she said, trying to comfort her friend. "It's part of growing up."
"Auuuugghhh!" Rainbow moaned. "But I'm young! I'm not supposed to be an old mare yet!"
"Sometimes it happens to some ponies earlier than others," Twilight said, putting a hoof on her shoulder. "It's perfectly natural."
"I know..." Rainbow replied, looking into her friend's eyes, appreciating the gesture. "Won't be long before everypony starts calling me 'Graybow Dash'. You... you think you could still change it?" Rainbow pleaded.
"Hmm. Well, let me see," Twilight said. She walked over to one of the many bookshelves in her home. Using her magic, she levitated a tome from the rack and brought it down to eye level. Rainbow Dash, airborne, began flying back and fourth near the cieling, the pegasi equivalent to nervous pacing.
"Aging magic is performable by only the highest-level unicorns," Twilight said as flipped through the pages. "But a chameleon spell should be easy enough to do."
Rainbow flew down to examine the book as Twilight turned through it. She could barely understand the symbols imprinted in the book, how Twilight did so was a complete mystery.
"Ah-ha, here. The chameleon spell, good for changing any color on any pony," Twilight announced as she arrived at the correct page. "I've never performed this magic before," she said, cautioning her friend.
"What're ya talkin about? You're a pro, Twilight!" she said, hoping a little encouragement would get results. "If anypony can pull off this spell, you can."
"All right, we'll give it a whirl," Twilight said. She closed the book and turned to face Rainbow Dash. "Are you ready?" she asked.
Rainbow Dash landed on the floor and stood with her head held high. "Ready," she replied, not an ounce of doubt in her voice.
"Okay, here goes," Twilight said. She squinted her eyes and focused on the tiny strand of hair silvery hair in Rainbow's mane. Twilight's horn glowed a bright magenta. Rainbow herself squinted from the brightness of the light but she kept an eye on Twilight, as did Twilight on her target. An aura expanded outward in a circle until it finally reached its peak. At maximum magical capacity, a ray shot out from Twilight's horn and struck the strand. The room was engulfed in a flash and just like that, it was all over. When Twilight opened her eyes, her jaw hit the floor.
"Well? Did it work?" Rainbow asked, trying to see her hair in front of her. What she didn't notice was her coat.
"Uh, Rainbow-" Twilight said, her voice almost trembling.
"Do you have a mirror or something? I can't see my mane." Rainbow looked around for a mirror or reflective surface to examine the spell's effect. Twilight flipped through the pages of the book again frantically, trying to find out what had gone wrong.
"Here we go," she said, grabbing a small mirror off Twilight's nightstand. She brought it to her face and thought there had to be something wrong with the mirror. Rainbow examined it carefully for a quick moment and then examined her reflection again. Not only was her mane a rainbow... but her entire body was too. Her coat from head to tail was a myriad of colors in various swirl, dot and stripe patters.
"Wha-what happened?! I... I look like a..." Rainbow Dash could barely form the words.
"I... I think I might've used the wrong chameleon spell," Twilight said. "I must've misread something somewhere." She flipped through the pages again with a worried expression on her face.
"You made me a chameleon?!!" Rainbow Dash yelled in exasperation. She examined her hooves, her tail, her entire body looked like an abstract art project. "You can fix this, right?!" Rainbow asked, hoping.
"Of course!" Twilight assured her. "Just let me... here we go," she said. She cast another spell on her friend and her body was engulfed in a magic aura again. Another flash burst fourth from Rainbow's body.
"Phew," Twilight wiped the sweat off her forehead. "Thank goodness that worked."
"What's that supposed to mean? I thought you said, 'Of course'!" Rainbow Dash grabbed the mirror and quickly looked over her coat again. Sky blue, rainbow mane... same glint of gray punctuating the bright yellow.
"Well I... I meant, of course I could fix it. But if that spell hadn't worked, it might've taken me a few days... and I might've had to consider paint and brushes as an alternative-"
"Paint and brushes?!!" Rainbow shrieked, realizing how serious her friend was. Rainbow Dash was a Pegasus, magic was not her area of expertise, flying was.
"I'm sorry Rainbow," Twilight said, trying to console her friend again. "I'm not really familiar with these kinds of appearance spells. Unless you want a moustache, that is."
"I think I'll pass..." Rainbow Dash said. "Thanks for trying, Twilight. I think I'll go now..." She slowly walked to the door and opened it.
"Rainbow Dash," Twilight stopped her friend in the doorway. "Maybe Zecora knows something about hair color. She's got potions for a lot of things, she might have one for changing your mane color," she recommended.
Rainbow Dash thought about that. "Thanks, Twilight. That's a good idea," she said. Zecora lived in the Everfree Forest on the edge of town, she could drop by her place and ask her. The zebra was known to have remedies for a variety of things so she just might have one for reversing the appearance of aging.
"Good luck, Rainbow Dash," Twilight bid farewell to her friend. "And let me know if you have any side-effects from that spell."
"Side-effects? What?" Rainbow asked as she departed Twilight's tree home.
"Oh nothing, what are the odds you'll start eating bugs? I'm sure you'll be fine," Twilight said.
"Wait, what was that?" Rainbow stopped and turned back.
"Nothing! Good luck!" Twilight shouted, closing the door. Rainbow Dash swallowed hard, kicked off from the ground and flew in the direction of the Everfree Forest.