They had just entered Loki's room. Thor put Mjolnir on the floor and sat on his brother's bed while he approached his collections of books and, picking up a red and blue one, sat next to his brother, opening it.

"Very well… Which book is that?" Thor asked, smiling with a cheerful and challenging look. Loki ran his hands over the cover of the object and opened it.

"Why don't you see it yourself?" Loki asked and sat next to Thor who lifted his eyebrows as soon as he saw the title - "Origin: The Ancient Theory"

"What?" Loki asked, innocent "You know I have always loved history!"

"I thought this book did not even exist anymore! Hadn't father forbidden you from reading it when you were younger?"

"That's because it tells us a lot about sorcery, Thor. The entire theory about the beginning of the Universe, about Yggdrasill's origin itself present in this one book comes from a world immerse in dark magic. You know how father... Loved... When I messed up with any kind of magic…"

"Oh, I see why you have hidden it so well… But why do you think it is going to be useful?"

"I remembered something I read a long time ago about the ability of becoming unseen and I think it is here somewhere…"

Loki had read that book five or six times and then forgot about it. Now, searching through the index, he saw what he was looking for and turned to page 115.

"The Yggdrasis" he started reading and Thor sat straight up, listening carefully.

"The first population to ever exist was of 'The Yggdrasis'. Its people mastered thousands of magical abilities, abilities which allowed them to create the Tree of Life and baptize it with their names. These people were the most powerful beings considering other irrational creatures already existed in their Realm, the realm of Yggdrasi. Being the creators of magic itself, the Yggdrasis passed their knowledge down to many generations. As time passed, however, they decided they needed to expand their power through other places and open the universe to their wishes. And then, Yggdrasil, the Tree of Life was born"

"Why have you never read this for me when we were kids? I mean, it is awesome!" Thor said with a smile. Damn, he would never grow up. He was better like this, anyway… After all, it was awesome!

"Hystory has aways been a favorite of mine…"

"Of course, you were always reading the interesting stuff while I was sent to study boring Literature!"

"Not my fault. In any case…" Loki continued, smiling.

"Many of the Yggdrasis soon moved to the other Realms they created to build new empires and be the owners of everything that ever existed. But soon the Realm of Yggdrasi became weak and the ones capable of using magic in such a devastating way soon forgot about their psychological abilities, deciding to become physically strong and build giant armies so they would be prepared if they weren't the only creatures of the Universe. Magic started to be seen as a weakness for it did not seem to be useful in wars. This would have been the reason for nowadays' rivalry between warriors and sorcerers. Since then, whoever uses magic is bad seen by the people"

"One day I will still learn that balance thing you told me about…" Thor said, feeling shivers as he remembered the poisonous snake that climbed up his leg while they were at the library.

"We are both important, that's the balance! There are warriors out there that can overcome so many sorcerers but the contrary also happens. Very few people can understand that, though…" Loki sighed. He knew it all pretty well; being one of the few magicians that still lived in Asgard meant trouble, of course, but he was used to it. In fact, he didn't care about whatever it was said about him anymore. He had other goals now and he knew magic would help him one day. He just did not know if it would be the best option…

"Easy as that?" Thor exclaimed "Why did you transform my book into a snake to say a such simple thing? You could have just explained it this way!"

"I could have explained it like this, true. But, the question is… Would you have believed me without any proof?"

Damn intelectual brother!

"As soon as the Yggdrasis started spreading appart, their knowledge started to vanish. The elders had no one to teach and the younger ones tried to become better physically only. However, to keep everything they had created related to sorcery in safety, a book was written and held within their defenses so if someone needed them it would still be accessible. The book, however, was somehow lost and it is said that, until today, it is lost between the Nine Realms, never to be found"

"Wait, so is that…"

"The Art of the Dark Shadows, yes…"

"Well, at least we know that last bit is a lie!" Thor said and shrugged. Loki grinned and continued.

"Even though some say the book truly exists, it is something we can have doubts about since the Yggdrasi Realm was never found. Those who believe in this theory, however, say that it just chose to disappear but it is still out there, watching over the Nine Realms created by its people"

"Chose to disappear! Chose to disappear, brother, it makes total sense!" Loki exclaimed "The Yggdrasis were truly talented while dealing with magic manipulation, they were the ones to develop it in the first place! When their people started spreading appart, they started searching endlessly for the book! It would be able to teach them the forgotten Arts again and recover their deserved place above the Nine Realms as their creators! But they were weak so they pretended to have vanished while they recover their strenght!"

"Yes!" Thor exclaimed loudly and, excited, continued "That would also explain the whole problem about the creature and the mist! They are looking for power again and the only way to have it again is by recovering the book! As soon as they realized it was here, in Asgard, they sent one creature, only one because they couln't risk losing more soldiers! So they sent the monster in here and it was slowly covering the whole Realm with Mist so all of us would become, ahn, blind, deaf and – Well, dead -. That done, it would be easier for them to recover the book and leave with no harm done to their armies!"

"They want to restore their Realm to its full glory so they'll finally be able to rule over the Realms created by them! Of course!"

Both were panting with excitement while looking to each other, smiling big while realizing what they had done. Both laughed.

"We are awesome!" Thor said with a high-five.

"Yes, we are!" Loki agreed, answering to the high-five.

"Should we tell father about this? I know it's just a theory we have but, well, maybe we should give it a try?"

"I think we should wait a while longer, Thor. Even if it looks like we are about to discover everything, just as you said it is all only our theory. But that is not the problem, brother…"

"It is not?"

"No… We lack the most important information about this and father would not want us to forget about this detail…" Loki turned to face Thor with a serious look and Thor knew what he was going to say before he did. His voice came with a dark tone and the deepness of the problem seemed to be a stumbling block.

"Who brought the Yggdrasis book to Asgard? And especially…

Why?"