"I think," Loki said smoothly as he guided the small group of frost giants through the paths of Yggdrasil, "you will find this a very fruitful endeavour."
"I have no doubts about that," the tallest, Hymir, smirked.
They emerged into the gold-plated corridor that led to the Vault. Wasting no time, Loki threw matching daggers into the necks of the two Einherjar who were standing guard outside the door. Boredom had slowed their reflexes and they could do little more than gurgle in surprise as they dropped to the ground. Loki rendered their bodies invisible and checked that they were all still hidden from Heimdall's gaze. He sighed in relief, everything was going well so far, with luck he would not be executed for this.
Now for the hard part…
"It is through these doors," Loki said, retrieving his daggers and wiping the blood off carefully on the guards' clothes. "Be careful, move slowly, there may be enchantments that I do not know of."
He turned away.
"Wait," Ymir called out, panicked. "Where are you going?"
"To distract Odin and buy us time," Loki lied, letting his hated blue skin fade away. He looked confidently at the frost giants, slipping on a mask of self-assurance.
"You are truly a gifted shape shifter," stated Hymir and Loki felt a flush of pride. He knew that such an ability was shameful, but he couldn't help the glow of happiness that grew in his heart at the words. He almost felt guilty at what he was about to do.
"Good luck!" Ymir smiled as Loki teleported away.
He reappeared just outside of the throne room and then made his way as quickly as possible to his place. He slid next to his mother who gazed at him angrily, lips thin in disapproval. He watched Thor tossing Mjolnir as he swaggered up the aisle. He didn't dare to look at the Allfather's expression. Loki just hoped that the unforgivable infraction of being late to Thor's coronation would be overshadowed by the Jotuns sneaking into the Vault and Thor's inevitable overreaction.
Thor had made his way up the aisle and was now kneeling before the Allfather, who was saying something about Mjolnir's might and how it related to Thor's greatness.
"Do you swear to guard the Nine Realms?"
"Do you swear to preserve the peace?"
"I swear!" Thor cried as Loki barely surpressed the urge to roll his eyes. Thor was never the type to pass up a chance of battle. That was why what he was doing was important. That was why he was risking everything to stop this.
But what was taking them so long Loki wondered, his heart racing. Yes, he had told them to take their time, he had needed to get back to avoid suspicion after all, but this plan would all be in vain were Thor to actually become king. If Thor were to become king he would only have made the situation worse. If Thor were made king, did he have time to get back to the Vault and stop them?
"Do you…" Odin trailed off and the room suddenly felt very quiet, very tense. Loki began to hope again. "Frost Giants!" Odin declared, slamming Gungnir into the ground. Loki felt a flash of guilt at the thought of his temporary allies (all of them had been strangely kind once he had gained their trust and had had surprisingly good senses of humour for monsters) but he quickly suppressed it.
Loki knew he was a monster, and the only way he could make up for that was by carrying out Odin's word.
He wondered, not for the first time, if going so strongly against his will was a good idea, before assuring himself that however much this might be seen as a betrayal, Thor could never carry out Odin's will the way he was at the moment. Odin had told Loki that he wanted to foster peace throughout the Nine Realms, and Loki was certain that, even though Odin wanted Thor to be king, with Thor on the throne the peace between the Nine Realms would never continue. Looking at Thor's outraged face he knew that Thor could not yet be the King that Asgard needed.
Loki stared down in horror at his dark blue arms. Where once his skin had been pale and smooth it was now dark with strange raised lines.
He stumbled towards his mirror and let out a cry of anguish. His face was the same shade of blue and the complicated lines adorned it too. But the worst thing about his new appearance was his eyes. They had been a beautiful deep emerald but now, now they were a horrifying, monstrous red.
Loki screamed in anguish. What had he done?
Father and mother will know what to do, he thought. He gathered up his spell book on shapeshifting and stumbled down the passage that connected his chambers to his parents' ones.
"Help!" he cried, shoving the door open.
In his terror he didn't see Odin's expression change from surprise to horror and disgust.
"Father, help, I don't know…I don't understand what I've done…It wasn't meant to change me into a monster!" he raced forwards, wanting to be held in his father's arms. His father had always been more reluctant to hold him than his mother, but his mother wasn't here, and he was sure he wouldn't deny him this, not when he was feeling so distraught.
"Loki, stop," his father said coldly. Loki froze, shocked at his father's tone, and gazed up at him in confusion. "Stay where you are."
"But Father I-"
"Silence!" he stared down at Loki in disgust. "What have you done?"
"I…I…" Loki choked. "I was practicing a shapeshifting spell…I wanted to turn into a snake…but then I felt something break and instead I turned into this! Please, please turn me back, I don't want to look like a monster!"
Odin stared at him for a minute, a calculating expression on his face. "Loki, you are a monster."
The silence echoed.
"What?" Loki cried. "No, no this isn't me! Change me back, change me back! Get mother, she'll know what to do!"
"It is you Loki," the Allfather said calmly. "You are a frost giant."
"No, no, I'm not!" he sobbed. "I'm not like them, I'm Asgardian, I don't eat children! Turn me back!"
"Cease your crying this instant," Odin commanded while Loki shook his head, refusing to believe his father's words. "You are a frost giant, Loki, you are a monster. However, I will turn you back, just so I don't have to look at your hideous form for longer than I need to."
"Thank you," Loki breathed, shuddering and trying to stop crying. Odin placed a hand on Loki's head and Loki could feel the familiar magic washing over him, he hadn't even realised it had been there until his spell had accidentally removed it.
"There," his father said at last. Loki sighed in relief, the horror draining away, and tried to hug him. Odin snarled, shoving him roughly and he fell to the floor. "Do not touch me Loki. You know now what you are, of the monster you hide within you. You cannot think that you are worthy to touch me!"
Loki struggled to his feet, the rejection hurting perhaps more than anything else he had felt that afternoon. But…if his father didn't want him anymore…what about Thor, what about his mother? "Please don't, please don't tell Thor, please don't tell Mother that I'm a monster!" Loki begged, tears streaming down his cheeks.
The Allfather lay a heavy hand on his shoulder, a mockery of comfort, of caring. "Well, as long as you are a very good boy and obey me, and stop your evil tricks and your magic, I see no reason why I should let them know that you are a monster."
Loki drew in a shaky breath and nodded, he could do this, he had to be able to do this, he could not lose Thor. "Yes Father, thank you Father, I will…" he cried out as Odin's fingers pressed into his collar bone.
"I am not your father, not when we're alone and there's no longer any need to pretend you are what you're not," said Odin icily and Loki nodded mutely. "Good. Now get out of my sight."
Loki fled, the spell book lying forgotten on the floor. Odin picked it up, smiling grimly. The situation, he thought, could have gone very badly, but hopefully now Loki would be easier to control.