Disclaimer: I do not own Game of Thrones or Halo. Game of Thrones is property of HBO and George RR Martin. Halo is property of Bungie, 343 Industries, and Microsoft... or something like that. Look, I don't own them, okay?
This idea of a crossover has been festering like a bad case of dysentery inside the bowels of my mind for about a month or two. I know, it's weird, but I do this for the purpose of indulging my imagination and also to see everyone's favorite Spartan opening five cans of whoop-ass. Be warned, however, as Master Chief is obviously going to make mincemeat of entire armies, throw the game of thrones completely wabbajack, and generally making every Lannister (hint hint) in Westeros brown their trousers when they realize the aforementioned cans of whoop-ass he will open.
Why? Because he can.
Anyway, we'll start our story just before the canonical start of the series...
The Forward Unto Dawn had been adrift in uncharted space for nearly three years, by Cortana's estimates-time had little meaning in the darkness of the ship's battered hull. The distress beacon slowly gnawed away at it's already waning power supply as they floated through the abyss, with no clear destination in sight. All the while, Chief was silent, slumbering in that coffin of ice and stasis, leaving Cortana alone to her thoughts, with but all the summed knowledge of humanity to occupy her time.
Until fate, chance, (lack of) luck, some combination thereof, or something else entirely, changed that. Like a ripple breaking the surface of a long-still pond, the monotone was broken.
The ship was being pulled into the gravitational field of a planet. The smart AI could have tried to change the wreck's course earlier, perhaps avoiding the pull altogether-but that was just the problem. The ship was a wreck. Even if she could revert their power supply to fuel the rear thrusters, Cortana knew that even to fire up the engines could drain the last reserves of power they had, silencing their distress beacon and leaving them adrift in the darkness of space.
By all accounts, the planet itself seemed hospitable enough. Cloud formations, vast bodies of water, three visible land masses from the ship's vantage point... honestly, it looked a lot like Earth, except for the formations of said continents.
"Sadly, no time for sight-seeing," Cortana sighed, "From what I guess, this'll be one of those close encounters."
Indeed, while the pull of the planet's mass was slow at first, momentum was building and soon the pull would become harder, their course running faster. She wagered they had perhaps less than an hour before they entered the planet's atmosphere. And if they were to be ready, to salvage what they could of their sorry situation... well, it was time.
"Time to wake up the sleeping beauty," She said with snark in her voice, but not without a smile on her face as she turned towards her long-dormant friend.
It was time for John to wake up.
Arya had managed to smuggle herself and a decent horse out of the castle without a hitch. It had been close, and only possible because she'd caught Harwin doing something he wasn't supposed to be doing, and had been all too eager to allow her to run off in exchange for her silence. It was actually rather funny how he was so flustered over some pretty little woman from the winter town, but Arya didn't care as long as she got her little moment of adventure.
She'd wondered off after Sansa and Jenye Poole had been particularly nasty to her during another of Septa Mordaine's dreadful sewing lessons, and was all too happy to distract herself-her mother's inevitable scolding be damned. She wasn't a lady, and wasn't going to let any of them make her try to be one. She'd ride, wear boy's cloths, and get dirty as much as she well pleased.
Sadly, it wasn't to last, because it seemed she had someone in pursuit. Jon was riding fast behind her, covering ground much more quickly on his black charger as he called out her name. A wicked smile broadening across her face, Arya turned her horse to gallop, hoping to out-ride her favorite brother.
For several minutes, she did, until it became clear Jon had both the better skill of riding as well as the sturdier horse. She puffed her cheeks as she slowed her poor, wheezing horse into a low trot, frustrated she'd been caught so quickly.
Once he caught up to her, she could see Jon had a quizzical look on his face. "Aren't you supposed to be sewing with the septa?"
To that, Arya lowered her gaze, finding her saddle to be quite interesting. "It's boring there. And everyone knows I stink at being a lady."
Jon only smiled. "Right, you are a little wolf," He laughed, reaching out his hand to her ruffling her hair. "One of the Starks of Winterfell."
She laughed, as she always did with Jon. Of all her siblings, only he didn't try to make her be a lady, encouraging her to do the things she liked. "You're my brother, so that makes you a wolf, too."
Jon's eyes became bitter at her words as he simply looked forward. "No, I'm not a Stark. I'm a Snow, nothing more."
"But why? You look more like father than all of us!"
"We've already talked about this, Arya," Jon said in a voice which brokered no further mention of the topic, guiding the both of them to a nearby pond along the road. "Let your horse drink and catch it's breath. Then we ride back for Winterfell. You're mother will be worried about..." His voice trailed off, his eyebrows furrowing in concentration, as though he'd discovered something amiss.
"Jon...?" Arya blinked at her brother, wondering what was wrong.
"Can't you hear that?"
She looked at him oddly. "Hear what?" But she didn't have to wait before her own ears picked up a most peculiar sound. It was distant, yet distinct-like a a low, far-off, but intense wind galling high in the air. All of a sudden, the horse became afraid, neighing and whinnying in increasing volumes of distress.
"I don't like this," Jon said uneasily. "We should head back."
Arya blinked, confused at that. "Wait, what is it? Is there a storm coming?" She looked up into the sky, trying to find dark clouds...
"Not likely. Winter may indeed be coming, but Maester Luwin says it's still a while off before fall. I think-"
"Jon, look!" Arya's eyes were wide now, her gaze fixed upwards.
Following her gaze, Jon looked queerly upwards-and his eyes widened. "By the Old Gods...!"
For up in the sky, it looked as though a terrible, fiery star-or perhaps a part of the sky itself-was falling fast towards the earth. And as it fell further down towards the earth, the noise intensified. And although she was scared, although she feared that it could fall down on her and Jon, or at their home in Winterfell, Arya couldn't help but gaze at it in awe. She'd never seen something like it before.
"Well, we can at least take comfort in the fact this won't be our first emergency landing," Cortana quipped within the confines of the recently-awakened John-117's helmet, her data crystal feeling much safer within the Spartan's armor than on that derelict ship, even as the Forward Unto Dawn breached the planet's atmosphere, set on a course for the northern part of the western landmass. "Didn't you go through this before?"
"Admittedly," John replied dryly, "I only had a flimsy piece of metal, not half a ship."
"Well then, this shouldn't be a problem for you. We've got less than a minute before we hit ground level, and we can't use any of the escape pods."
"We'll make it," He assured her in his simple yet sincere confidence.
"...I know I said this before, but I sure know how to pick 'em." If she had a mouth, Cortana would have smiled at that moment. Even with the ship's hull burning as it ripped through the sky, even as the ground came upon them closer and closer, she could take comfort in this one man's presence.
It was just the kind of man John was.
On that day, when the wreckage of the Forward Unto Dawn landed in the North, midway between Torrhen's Square and Winterfell, was like a mountain crashing into the sea. For though the earth's shaking when the colossal mass of metal impacted the land could be felt and heard for miles around, it would pale in comparison to the waves which would ripple throughout Westeros in the coming months and years.
For on that day, the mightiest hero Westeros would ever come to know arrived, and this stranger from another world would make the realm tremble before him.