Author's note: This is written for the Quidditch League Fanfiction Competition (Round 12) "Blurring the Lines". This is only my second crossover so I hope it's a good idea. The Marvel films are some of my favourites so I'm linking them to Harry Potter :) I do appreciate reviews!

Task: Write a crossover with another fandom from the 'movies' category - Thor

Prompts used: (phrase) now or never, (dialogue) "Who the bloody hell is that?" and (word) eyelash.

Disclaimer: I do not own Harry Potter or any of the characters therein.

"No, Ron! You've got to really concentrate!"

Ron exhaled sharply at Hermione's comment. Harry, Ron and Hermione had been sat by the roaring fire in the Gryffindor common room since dinner, but it was now almost ten o'clock and Ron still hadn't mastered the spell. Darkness had been imposing itself upon them since late afternoon, now leaving only the flames to provide light to read and work by.

Snow had begun to settle in the corners of the glass, outlining the frosted pane in soft, white crystals. The Christmas holidays were only one week away and the increasing amount of snow added to the festive feeling in the aged castle.

Professor Flitwick had informed the class a week previously that he wanted to see each and every one of them perform a charm that would make one item from another room appear before them in their own classroom, before the term ended.

The summoning charm had been banned from that particular test as, as soon as Professor Flitwick had announced the task, Seamus Finnigan had used that exact charm to pull half a dozen tables and chairs into the doorway from the next room.

Hermione, of course, had mastered the spell immediately and it had only taken Harry a few days to get it right too. However, the red-haired boy was having a lot more difficulty.

Ron huffed again, as still nothing seemed to happen when he said the incantation. The test was tomorrow, so it really was a case of 'now or never' or else he'd would be stuck with double the amount of holiday homework of everyone else.

"Focus, Ron," Hermione said again, for what felt like the one hundredth time, "picture it in your head. The green and black striped jumper. It's lying exactly where I left it on your bed. Just imagine it disappearing from there, and landing in front of you."

Closing his eyes, Ron imagined the jumper laid neatly across his scarlet blanket. Green and black stripes. Green and black…

His eyes still closed, he spoke the incantation aloud, waving his wand in a correct flourish. He quickly opened his eyes, desperately hoping to see the knitted jumper sat in front of him, but there was still only the empty yellow bowl that the three of them had cleared of Honeydukes' latest creations.

Looking towards Hermione, Ron expected another lecture on the importance of pronunciation, but instead was met by silence. Not just silence from his friends though, as all the chatter from the remaining students in the room had died, leaving the place eerily quiet. Hermione's gaze, as well as Harry's, was fixed on the centre of the round room.

A figure stood in the middle of the ancient crimson rug, silently surveying his surroundings. He must have been around six foot in height, towering far above most of the other people in the common room. His jet black hair was swept off of his face, slicked back against his head, falling to just above his shoulders. He was clad from head to toe in black and green fabrics, with the occasional flash of gold illuminated in the fire light. Dark eyelashes highlighted his piercing green eyes, which continued to sweep around the scene before him.

"Okay, very funny, Thor," he said, as he started to wander about the room, though his words seemed to be directed at the ceiling, "an excellent trick, but there is no way in the realms that you did that without help."

No one in the room said a word, though the visitor was acting as though all of the quivering students did not exist. Some tried to withdraw themselves from the room, inch by inch, but were too scared to move with any speed. Others shrank back against the walls, hoping that the intruder would not notice them if they pressed themselves flat against the worn tapestries.

Ron turned back to Hermione, who looked a little timid, but more intrigued by the sudden appearance of the dark-haired stranger.

"Hermione, who the bloody hell is that?" Ron asked quietly, trying to not catch the attention of the man who was still talking to the stone ceiling above.

"I don't know. Oh, Ron, you must have been concentrating on the colour of the jumper too much and brought him here instead," Hermione answered, her eyes following the figure as he took careful steps in the centre of the rug, "I mean, look at his clothing!"

Ron looked again and saw that the stranger's clothing did look a lot like the jumper that must still have laid abandoned on his four poster bed.

"But that means…" Ron said, starting to realise the importance of what he just did, "that means I actually did the spell! I did it!"

He grinned widely at his success, but Hermione instantly shot him down.

"You did not do it! You were meant to bring that jumper downstairs, not make some poor man appear in the middle of our common room!"

The raised voices finally caught the attention of the outsider. He strode over to where Harry, Ron and Hermione sat, silencing them all instantly.

"You, there," he said, pointing to Hermione, his crisp voice and superior tone making the words sound incredibly commanding, "where am I? Is this Midgard?"

Hermione gulped, but sat up straight in the armchair she had occupied for the majority of the evening.

"You're at Hogwarts, sir," she started, her voice coming out fairly clearly, but her trembling hands gave her terrified feelings away, "It's a school for… magic… in Scotland."

She did not know what 'Midgard' was, so had no way of answering the latter question. The stranger seemed to gage enough from her answer to be satisfied. He nodded curtly and turned to walk back to the centre of the room.

"Sir, if you don't mind me asking," Hermione said, finding her courage and lifting herself from the chair to stand up in front of it, "who are you?"

Harry and Ron tried to hold her back, not knowing what the stranger would do if he did not like the question Hermione posed. But, he seemed to think it perfectly reasonable and replied.

"I am Loki of Asgard, and I believe that my brother, Thor, has played a prank on me, that I'm sure he will tease me about for the next half century or so," Loki said, a hint of sourness evident in his voice.

Hermione nodded slightly, unsure of how to reply to his words, knowing that he was mistaken. Loki would quickly find out that his brother had had nothing to do with his sudden disappearance from Asgard. He quickly removed his gaze from Hermione's and looked directly at the sky again.

"Heimdall, open the Bifrost and bring me back," he said, standing very still, as though he knew that something would happen when he said this.

Suddenly, there was a bright flash of rainbow coloured light. Everyone in the room shielded their eyes from the dazzling spectrum, and when they opened them again, Loki was gone. In his place was an intricate, circular pattern which covered half of the floor in the room.

The trio rushed forwards and stood around the charred rug, watching as the glowing embers started to turn from red to black in the swirling pattern that marked the floor. Both Harry and Hermione turned to Ron; their expressions were horrified.

"So," Ron said sheepishly, "who wants to explain that to Professor McGonagall?"

A/N: Okay, so it's a tiny bit pointless, but I still enjoyed writing it. Please leave a review, because I really like to know what you think. Thank you for reading :)

Thor: In case you haven't seen Thor, here's a very quick summary (though you should really go watch it, along with the other Marvel films because they are really good): It's a kind of re-telling of Norse mythology, so Thor is the son of Odin and is incredibly vain and isn't really fit to be a king yet. Loki is Thor's younger brother and gets really jealous when Odin says that Thor should be king soon, as Loki believes he would make a much better king. When Thor does some reckless things, Odin banishes him to Earth to learn some compassion and humbleness and Loki tries to do everything he can to keep Thor on Earth, so he can take over. It's really good and you should watch it. This story is set before the film starts, when Thor and Loki are still friends and everything was happy.