It wasn't the fall that broke him.

It wasn't the envy or the anger.

It wasn't even the Chitauri.

It was time.

Thor had realized that as he watched Loki through the glass prison door, his little brother's head hung low as he slept. Though Thor wouldn't say it was sleeping; it was much too stiff, too restless to be truly be considered sleep. But then by that definition, Thor never slept either, or rather, never slept since Loki's fall.

That wasn't because Thor was broken, however. No, Thor was not broken like Loki, and that was one thing he was positive on. He did not have those dark angry circles around his eyes that were more than just from lack of sleep. His hair, though getting quite long, was not snarled and knotted from his lack of caring nor will to care like Loki's. Loki was broken, not Thor.

But Thor had already known that; it was obvious. He just hadn't known what had twisted his little brother the most.

Now he knew.

It was the wait. The year he had spent after the fall when he was all-alone. All alone except for the Chitauri and the memories.

Thor did not know what memories Loki dwelled upon, nor what perspective he viewed the memories that Thor found so dear, but time can easily twist two identical memories into something entirely different; something quite dissimilar from the original that it seems almost impossible that those memories were once the same. It can turn bad to good, or good to bad, it just had the power to do it. No, the memories didn't twist Loki, they were simply a tool to help with the job.

And the Chitauri, they acted just the same as the memories. They were simply tools, speeding the memory twisting process along. Whispering little jabs in his ear, encouraging the bad thoughts that were already budding in his head to bloom into terrible flowers. Horrible plants. No, the Chitauri were simply catalysts.

It was time that had done the true work. If only Odin had told Loki the truth, than time would never had been able to grow the disgust inside. Or rather, Thor, Odin, and Frigga would have had more time to explain. If only Thor had been able to hold on to Loki, they would have had time to ensure him that he was their relation even if it wasn't in blood.

Time didn't let them, however, Loki had let go and the opportunity, the time, had slipped from their fingertips. Suddenly, Loki was alone, with only time to be able to forget what was really there and create new memories. New false memories that would cause his anger to grow and twist Loki into something that would destroy. Would kill.

This Loki, that slept so unpeacefully, was merely as shadow of his former self, Thor thought to himself as he slowly leaned his head again the glass wall and sighed. This Loki could not see that Frigga and Odin took him and raised him as their own son, not as a relic of a past victory. This Loki could not see that the whole of Asguard had seen him as their own prince, not a monster or their enemy. And this Loki could not see that Thor did and would always see Loki, the real Loki, as his brother, not his adopted brother, but his own flesh and blood.

But it was too late. Loki had forgotten what had really happened, time had taken it away from him. And only time would bring it back. No matter how much they talked with him, no matter how much they begged and reasoned. Time took away the truth and only time could give it back.

But how much time would it take? Months? Years? An eternity?

Thor did not know, nor would he ever know. But what Thor did know is that he would never give up, because this mangled twisted person in front of him was not his brother. His brother was still in there, hidden among the thorns. And Thor was going to pull him out and would battle time until he won. Because Thor had never lost a battle, and he wasn't going to lose the most important one he had ever fought.