Hello, Random Gamer!  I’m here on behalf of WRITE, as per a request  to review this story.  Let’s get to it, shall we?

Twilight, as the student she was, spent most of her time in her library and occasionally helping her friends when needed. But even as a skilled magician she was, she was also prone to accident and one involing the trunk of the tree triggered something she wasn't aware. She accidentally flung Spike and instead of him flying away, he made a hole in the trunk. Twilight, knowing he might got hurt quickly ran to him.

To begin, there is very little in the way of exposition.  The story begins almost immediately with Twilight having found a spellbook conveniently hidden in the trunk of the library, after an unexplained mishap involving Spike.  It leaves everything to the imagination and gives the reader nothing to draw upon, or for that matter, a reason to keep reading.  In fact, the entire narrative has little to offer the reader.

"Okay." Spike took a nap and Twilight spent several hours reading the before finding something which caught her attention. She carefully approached Spike and spoke silently.

"Spike, I found a spell I really want to test out." Spike jumped to his feet.

"Yes?"

"I'm going to need someone to test it on. Two volunteers to be exact.."

"Well, since there's no else here, I'll volunteer."

"Sorry Spike, I need someone who's a pony."

"Oh, right. It's always about ponies. I'll return shortly." Spike left the library and then returned half an hour later with Rainbow Dash and Fluttershy outside.

"So, Twilight, what do you need help with?" asked Dash.

"An old spell." she answered. "Not sure what exactly it's going to do."

"Oh, my. Are you... are you... sure that it's safe?" asked Fluttershy, scared.

"Don't worry Fluttershy, it's called Tria Carmina Inverta, which roughly translates to three inverted songs."

The above is an example of what is called “Talking Head Syndrome,” wherein speakers of dialogue are either poorly attributed or otherwise given no actions outside the words they speak.  The problem with this is that the reader can’t infer any information about what is happening or how a certain character feels about a situation.  All we know is what they say, and oftentimes in this fic that is only expounded by the odd dialogue choices the characters make.

"Umm, Twilight, are you sure you want to try any of the old spells? They could be dangerous and I kinda like you." said Spike.  Twilight blushed a little and smiled.

How exactly does Spike like Twilight here?  This comes from the beginning of the story and has little to go off of other than the normal brother/sister relationship they have in the show.

There are numerous grammatical errors throughout the story that hinder readability.  From missing capitalization to punctuation, simple slip-ups mess with what should be easy to read.  I’ll say it improves as the chapters progress, but there’s no reason it can’t be better than it is.  This website can help you immensely, as well as getting an editor for your work.

But with those things out of the way, let’s talk about the elephant in the room, the story itself.  The premise is a tired one: Twilight causes problems with her magic.  The idea of elementals and the like is a fresh twist—one I could see myself reading and thoroughly enjoying—but the presentation of the narrative is the biggest downfall of this story.  It is mostly a reflection of the above-mentioned lack of description.  There really isn’t any whatsoever.  And what little there is simply tells the reader what is happening:

Without hesitation, Twilight woke up, stole the book from Spike's grasp while he was asleep and started looking for the spell. Although she was quite sceptical in such matters, she was sure what she was doing was right.

The entire story is filled with this.  The story needs to give information through actions, not telling the reader how a character feels or what happens; show what happens through descriptions and let the reader decide if its scary, funny, amazing, happy, sad, or any other adjective you can think of.

In addition, the lack of narrative causes problems with pacing, as the entire story happens far too quickly (see your introduction paragraph).  You need more information about what is going on throughout.  Give some detail to how Twilight might have crept up to Spike while he was asleep after her dream, for example.  The actions, especially in the final chapters, need more to immerse the reader in your story.

And finally, what exactly does the ending of chapter one have to do with anything?  Referencing the “Move Like Jagger” song does nothing for the story, and, in fact, hurts any chance for accumulating a reader base.  A story should never break immersion by drawing the reader’s attention to something outside the story.  That is why memes are often frowned upon when referenced in stories.

As it stands, this story needs a lot of work.  The biggest factor to focus on, if nothing else, would be adding descriptions to what is happening in the story.  From there, everything else is simply practice.  I hope this review was helpful and that you seek to improve your works both now and in the future.

P.S.  As the advice above is very all-encompassing and changes to their affect will be rather large, I'd be happy to look at this again outside of WRITE after a thorough rewrite.

Corejo, WRITE's Arms Warrior