The Xenomorph Queen hissed in pleasure. No sickly, grey beings pervaded her hives now. They were diseased, scrawny things who could put up little resistance against her drones. The eggs she’d laid put them to good use, though. Their feeble weaponry, slings and bows by her estimation, could little pierce the hide of her children. She had lost a few, it was true, but they had served their purpose in the end.
Now, she reached out telepathically in the night, sending visions of herself far and wide to entice newcomers to her hive, that she might make them of her own. She could feel their differing physiologies; the material they would bring unto her would be extensively useful.
Her first outsider quarry was a group of stout biped men with weapons befitting their stature. They’d posed some small challenge to capture, but she would allow a few to escape: at least, after they had been impregnated, and she would stay the hand of her hatchlings until they had returned to their homes. Then, she would allow her seed to propagate similarly across the planet.
For, of course, this was her only objective: Control the planet through her progeny. And there was plentiful wildlife to turn to her own, from grey-blue, violent bipedal creatures to proud, strong, long-maned, hooved quadrupeds. They all fell to her dream assault, her immense telepathic presence turning her into their deity. They marched en masse into the mines to be turned, their numbers becoming hers as they were impregnated and parasitized.
Word had begun to spread among the kingdoms of a terror inside Moria. The tales told of a great dark monster with crystalline teeth and a black crown, who turned men and beast alike unto its brood.
The problem in the kingdoms’ communications came in the form of secrecy and deceit: None were willing to admit that their dreams had been pervaded with terrifying, awe-inspiring images of this Lord of Night, as they had taken to calling it. They could see it in their sleep, feel its presence looming in their mind when they were waking, and perhaps most frighteningly, they were hesitant to kill it, as it exuded magnificence and power, and to attempt its destruction may only incur its wrath and end its splendor.
Thus the delegation at Rivendell, excluding those who had once felt the corruption of the One Ring, spoke endlessly of containment over eradication. The kingdoms of Gondor and Rohan were represented appropriately, but not by those men who had felt the vitriol the Ring evoked. Thranduil himself appeared to represent Mirkwood, and Elrond was the host of the invoked gathering. A near-nameless dwarf king represented his entire race, and the Hobbits didn’t bother to send a delegation. No other races had been invited or informed to appear to discuss the greatest evil since Sauron begat the War for the Ring. Ergo, neither orcs, goblins, or werewolves, nor trolls, ents, or spiders were allowed to discuss their fate, as the elves detested them each but for ents, whom they respected but thought their numbers too few.
In essence, the Fellowship lived on in memorial action, though many of the peoples of Middle-Earth had fallen back into their ways of petty discourse and war.
In Rivendell did the convention speak in hushed tones, fearing the inferring of fear amongst their number by another, in that such a showing would emplace weakness upon their people in the minds of potential enemies.
And so, speaking from false boldness, the many chose to send forth parties of their own toward Moria, to collect in Rivendell and ride southward thus.
In one month’s time, the assorted factions had gathered themselves for a journey to Moria from Rivendell and marched forward, spirits beginning low as their visions of a desolate future under the Lord of Night where its spawn reigned made them more certain of their failure.
The Queen met their forces with several thousand of her own drones and warriors taken from the miles surrounding Moria. Her brood had converted the mines’ walls to a resinous compilation of her own making, which allowed them places to hide and ambush them as her forces feigned weakness, gathering inside the mines for the war party to follow.
“Thus we must take this task above all others upon ourselves: To slay the Lord of Night and bring an end to the terror of its brood. Who among you cannot speak to the horrors you have endured to reach this place? Not one, I can be assured. It is not in spite of your ordeals, but because of them, that you have found the courage—nay, the will—to fight to end night’s reign over Middle-Earth. It is for you that I raise my sword, and for each other and all others that you must as well. By the end of our great mission, each and all of us will be as the great heroes of old!”
Aragorn punctuated his speech by raising his sword. Fifty thousand men, dwarves, and elves raised their swords with him.
So, in summary: fifty thousand men, dwarves, and elves, led by Aragorn, have to enter Moria, navigate the mines, and fight about ten thousand drones and warriors before finally reaching the Queen in the deepest part of the mines and killing her as well.
Assume the numbers to be something like 40,000 men, 9,500 dwarves, and 500 elves, and 8,000 drones, 2,000 warriors, a handful of praetorians, and the Queen.
Of the Fellowship, only Aragorn and Legolas are present.