When the reports of living dead in the Nordic regions first reached Olympus, the gods did nothing.
It wasn't their concern, even if some of them were reported to wear greek armor. It was the duty of the Norse Pantheon to look after their lands and it was not their place to intervene.
But when they started to mention that the undead had been speaking of their great king, they suddenly started to get somewhat nervous. Even more so when they realized how far they had let his influence spread.
Groups of indigenous people throughout an area that stretched across the Nordic regions, through Russia and into Alaska had begun to worship this powerful entity as some kind of death god. The description of the entity in question did nothing to put their minds at ease.
A tall warrior clad in plate-armor and wielding a mystical runeblade with the power to control ice, acting as the supreme overlord of the complicated hive-mind that allowed the undead hordes to operate as efficiently as they did.
And to make matters even worse, it soon became clear that the mysterious king possessed the power to revive the dead. The horrified messengers had spoken of how the dead rose at the mere sound of his voice, eagerly following their new master.
The living followers, now known as the Knights of the Ebon Blade, were not afraid of death whatsoever and remained firm in their belief that they would live forever in their lord's service once they casted off the shackles of their mortal shells. A discovery that had been somewhat startling was that this 'mortal' who fashioned himself a god seemed to deliberately invite those that everyone else threw aside into his fold, the ones who existed at the bottom of society's social ladder.
And right when they thought that the situation couldn't get any worse, bizarre monsters of many different shapes and sizes had been sighted in the Greek Isles. They did not act violently, yet they patiently lied in wait. Like predators observing their prey.
Then one day a patrol encountered a gathering of monsters dangerously close to Camp Halfblood.
And from there everything just spiralling downward further and further...
-line-
Annabeth frowned as she walked down the corridors of Camp Halfblood with Davos by her side, somewhat irritated that she had pulled him away from his training.
"This has better be good, Anna..."
She looked at her partner with a sigh and an eye roll.
"Have you not heard? The scouts found a group of monsters close to the camp and now they want us to interrogate the prisoner they caught. They think that the group belonged to that cult that popped up recently, the one that worships that undead king."
Now Davos suddenly looked a tad more interested. He had heard plenty of rumors about the existence of a powerful king who ruled a kingdom of ice somewhere far north. Perhaps defeating such a foe would get him enough recognition to forever be recorded in the annals of history, perhaps he would even get a constellation named after him...
The duo arrived in the dungeon where a creature that greatly resembled a minotaur was chained to the wall, in spite of its many gruesome injuries it acted like they didn't exist and merely muttered to itself. As the two young gods approached its cell, it suddenly became quiet and stared in their direction. Its lifeless eyes looked like they were made of glass and an cold blue flame burned within them, it was an unsettling sight to say the least.
Davos stepped forward with a cocky smirk, eager to get going so that he could get back to his training as fast as possible.
"So, you foul creatures thought that you could step onto sacred ground without any consequences?"
The monster didn't respond whatsoever. Davos then stepped closer and forcefully took hold of the beast's horns in a show of intimidation.
"Let me make one thing clear. The only reason that you are still alive is because we believe that you possess information that could be of value to us. So it would be in your best interest to cooperate, otherwise..."
Davos put his hand on his sword to empathise his threat.
"...your head will roll."
The response Davos got was certainly not the one that he expected. Deep, hoarse laughter echoed though the cell and the God of Champions was slightly taken aback.
Then it spoke in a voice that felt colder than the winter they had just experienced mere weeks prior.
"It matters not whether this body lives or dies, my king will take care of my spirit and give me life once more. And my king is much greater than any of you, I will never betray him for anything you can offer."
Davos' face twisted in anger and he punched the creature in the face so hard that the sound of bone cracking became audible.
"Watch your tongue! You are speaking to the God of Champions, no wannabe ruler can ever be a match for me! I will tear him to shreds and reduce his kingdom to rubble!"
More mocking laughter escaped the cracked teeth and bloody lips.
"The King of Northend is more powerful than you can ever imagine, you wouldn't have a chance against him in battle. Even now as he watches from the Frozen Throne, he can sense the difference in power between you. A battle with you would be nothing but a waste of his time."
Annabeth who had been silently observing in the corner suddenly moved closer, showing great interest in the minotaur's words as she unintentionally saved it from yet another brutal beating from her furious partner.
"How can you know that? Your 'lord' is miles away from us."
The smile she got in return made her skin crawl.
"Very simple my dear, our minds are connected. Separate, yet acting as one. And the Lich King is the root who holds us together. He sees all that we see and hear all that he hear. And right now he is laughing. Laughing at the mere idea of him being defeated by any of you."
Simultaneously angered by the creature's words and horrified by their implications, Davos beheaded it in one swift motion. The body crumbled into a heap as the head landed in front of him, the flame fading from its eyes.
Anna looked at Davos who in spite of his seemingly calm exterior was clearly just as shaken as she was.
"We must go to Olympus, the gods have to know about this."
Rigidly nodding, he followed his female companion out of the dungeon as they hurried to deliver the important message.
-line-
The atmosphere on top of Olympus was incredibly tense as the youngest members of the Greek Pantheon retold the events that had unfolded.
Zeus frowned.
"It truly is troubling that you were not able to get more information out of that monster. However, given what you have revealed to us perhaps it was for the best that you exterminated it before it were able to give its master more information about us."
Athena suddenly caught on to one specific detail in that story.
"Annabeth...didn't you just say that beast referred to its master as the Lich King?"
The girl nodded, causing the chamber to filled with fearful whispers. Athena turned to Apollo who was sitting at her side, trembling as he paled in horror as the implication of her words sank in.
"Apollo...your prophecy...it is coming true!"
Annabeth looked up at her mother in confusion.
"What are you talking about, mother? What prophecy?"
The Goddess of Wisdom sighed.
"Five years ago, Apollo here beside me delivered a prophecy that spoke of an undead entity called the Lich King and we fear that his coming will bring destruction and unspeakable horrors. Already the longest winter have ended and the presence of the undead on the mainland means that the wall of ice must have broken apart. We don't have much time..."
"And it gets even worse than that."
Every eye was turned to the origin of the new voice, which turned out to be a recently arrived Hermes who was leaning against the doorway.
"I recently spoke with Hades regarding the issue of the undead and I learned something very disturbing."
Zeus leaned forward.
"Continue, Hermes."
Hermes took a deep breath, bracing himself for delivering the horrible message.
"The people that pledge themselves to the Lich King, whether it is the undead of Northend or the new followers in the world of the living, their spirits don't reach the river Styx when they die."
Here he turned to his fellow deities with a grim expression.
"Their spirits remain here on Earth, drawn towards the Lich King's domain where they are eventually reborn as living dead. They don't reach Elysium at all."
The gods spoke in fearful whispers and Annabeth frowned in concern, this was bigger than they could have ever imagined. Still, there was something wrong here. She was missing a piece of the puzzle. Something important...
"Apollo, what were the exact words of the prophecy?"
The god sighed and repeated the words that kept haunting him. He then continued to speak in a worn and tired voice as he tried to purvey its meaning.
"I believe that the lines about the mountains crumbling refers to the destruction of Olympus. Unfortunately, the prophecy does not reveal a lot regarding the identity of the king in question. There is however a lead regarding the so called 'blade of sorrows'."
Apollo turned towards Hephaestus who nodded and continued where his fellow deity left off.
"The words in the prophecy as well as the reports we have of the sword's abilities tells me that we are not dealing with any ordinary piece of metal. I dare say that the weapon that is wielded by the Northern King can be none other than the legendary runeblade Frostmourne."
A shudder went through the ones gathered as a cold wind blew through the chamber, almost as a response to the name being uttered. Davos seemed to pale slightly as he turned towards Hephaestus.
"The cursed blade?"
The old forger nodded.
"Forged from a frostgiant's corpse and ore mined within Hel, the norse land of the dead. From what I have been told, it was gifted to the king of a powerful viking-tribe by the Norse Gods in gratitude for his loyal service. It made him almost unstoppable and he laid waste to all who stood in his path, there was a time where he was considered to be a god in a mortal's body. However, everyone who has tried to claim the blade after his passing has either lost their mind or suffered a horrific fate."
Davos frowned.
"And now someone else has picked up where that old warchief left off."
Anna nodded and then she spoke in a grave tone.
"There is however one thing that is very concerning."
Everyone's attention was on her.
"The line about this king being born of sacred blood suggests that he is a halfblood. And last time I checked there is currently only one living halfblood that not present at the camp."
Davos turned to her, not liking the direction the conversation was going in.
"You can not be serious, Anna. Are you seriously trying to tell me that Percy might be..."
"He is still born of sacred blood, Poseidon's blood. And let us not forget that he was banished to Northend, the place where all of this madness originates from. There can be no one else."
Zeus cleared his throat and silenced the two youngsters with a stern glance that left no room for discussion.
"Regardless of whether that disgrace lies behind the Northern King or not, we can not allow him to continue with his conquest nor his careless meddling of the natural order. You two will go with the Hunters of Artemis to stop him. Depart for Northend as soon as you are able."
His tone signaled the end of the meeting and as Annabeth and Davos left to prepare for the battle that was no doubt awaiting them, the goddess couldn't help but to ponder on the past.
Even after the trial and unveiling of his horrible actions, she could not shake the young man that she had once loved out of her head. Nor the look of absolute shock and terror that had been present on his face as his crimes were laid bare before him. Part of her wanted to believe that he was innocent but Zeus' judgement was absolute and everyone else was convinced of his guilt so she had to put her personal feelings aside and allow justice to be delivered.
Now as she prepared to face the terrors of the forsaken island, she looked up towards the heavens hoping that somehow finds the answers she sought within the gathering of clouds.
'Percy, if you truly are the Lich King...forgive me...'
How do you like the new backstory that I made for Frostmourne? It felt appropriate somehow to have it be connected to Norse mythology given its connection to ice and the warrior-culture of the vikings.