Prologue

Harry

The first thing Harry Potter did when waking up was looking outside the window.

Is it gone… Harry deflated when he noticed that the fog was still there.

Harry did not understand this at all. His fourth year had just ended in June, and while he wouldn't say it was peak summer at this time in Britain, it certainly shouldn't be getting foggy so early.

Not to mention the fact that it did not feel cold at all. He could walk outside with nothing but a shirt and not feel even a nibble of cold.

Yet, the fog's just there.

Harry didn't need hints to know this was not a normal occurrence.

But what could it be? Is it some form of powerful magic that's been cast over Britain? If so, then who cast it? Harry thought before immediately scowling.

"Voldemort." He muttered. Who else could be powerful enough to cast a spell like this?

Harry grit his teeth at the memory of Cedric's lifeless corpse, him staring helplessly as the Hufflepuff was struck down by Voldemort.

I'm going to see what's so wrong about this fog today. Harry thought.

Harry got up and went about his morning routine and went downstairs.

Aunt Petunia and Uncle Vernon ignored him as usual, going about their own work. Harry noticed his breakfast was on the table and quickly ate.

Soon, he noticed Dudley come down the stairs.

"Good morning, duddy!" Aunt Petunia spoke with a smile as Harry rolled his eyes.

Well, here's to another day. He thought with a sigh.

Dudley sat away from them at the table and they ate quietly. Dudley would send glares at Harry from time-to-time, but Harry knew as long as he did not open his mouth, Dudley would not harass him…at the moment.

After breakfast was done, Harry went to the front door.

"And where are you going?" He heard Uncle Vernon's voice speak up.

"Just…getting some air."

"It's foggy outside, even if it is very odd."

"Well, it's not cold." Harry replied as Uncle Vernon stared at him with a bored expression.

"Hm, be back before lunch." He grunted as Harry went to walk out.

"Oh, wait! I'm coming too!" Dudley spoke up as Harry's jaw tightened. He knew exactly what Dudley wanted to do.

"Duddy, dear, I don't think its safe to go out in such dense fog." Aunt Petunia spoke.

"Don't worry, mum. If we're after spending time with Potter, the fog won't be too bad." He spoke, trying his best to butter up to his mother.

Harry bristled at the jab as Aunt Petunia sighed. "Half an hour, Duddy."

Dudley smiled. "Thanks, mum!" He spoke before walking up beside Harry.

"Come on, freak. Let's go outside." Dudley spoke as Harry shook his head before walking out.

And as soon as he did, Dudley began yelling.

"MUM! THERE'S A DOG STAMPING ON THE GARDEN!" He yelled as Harry looked at a black street dog walking around in their garden.

As soon as he came up, the dog stopped and looked straight at him.

Harry felt uneasy as the dog continued to stare at him without blinking once.

"What?!" Aunt Petunia's scream came from inside as she ran outside. Uncle Vernon came out as well. The dog did not break away from its stare and before Uncle Vernon could chase it away, it ran off into the fog.

What a weird dog. Harry thought as Uncle Vernon and Aunt Petunia went back into the house while Harry and Dudley walked out into the street.

"Alright, Dudley, what is it?" Harry asked with a sigh. Better to get Dudley off him quickly so that he could look more into this strange fog.

"You have some to do with this, don't you?" Dudley snarled as Harry blinked.

"The fog?"

"Yes, the fog! It's August! We shouldn't be having fog! And it's not cold! I could take off my shirt right now and not feel a thing. This isn't normal, which means you freaks have something to do with it!"

Harry's fists clenched. "I have nothing to do with this, Dudley." He replied.

"Oh really? You're saying this fog wasn't caused by you and your freaky friends?" Dudley asked.

"Dudley…"

"We've seen what you can do in the house. Every year you come over, you do some freaky magic and make us look like idiots!" Dudley snapped. "And this fog is your yearly gift, right? I haven't been able to go to school because of this stupid fog. You've really outdone yourself this time, Potter."

Harry glared. "I'm not that powerful, Dudley! I have nothing to do with this, and if you can't get that through your thick skull, then sod off!" Harry snapped, as he unconsciously tapped into his magic.

Dudley started to sweat as he shook his head and stepped back.

"Freak, like your dead mum…" He muttered under his breath as Harry's eyes widened.

"What did you just say?!" Harry spoke seething in fury as he grabbed Dudley's collar.

"Oh, you want me to repeat it for your blocked ears? I said 'Freak, like your dead mum'."

"You leave my mum out of this, Dudley." Harry in a cold voice, resisting the urge to punch Dudley in the face then and there.

"Please, your mum being out of this is a blessing to us all." Dudley replied as Harry went quiet as he reached his breaking point.

But before he could take out his rage on Dudley, barking reached his ears as Harry suddenly found himself surrounded by black dogs similar to the one he saw at the house.

What the… Harry thought as the dogs growled at him and Dudley.

"Hey, Potter." Dudley spoke with a hint of fear in his voice. "Call your dogs off."

"They're not my dogs, you idiot." Harry hissed.

"Why did they appear all of a sudden, then?!" Dudley spoke in panic. "Get out of the way, you stupid mutts!" Dudley snapped trying to run past them, before screaming as the dogs barked and snapping at him.

"What's gotten into them…" Harry muttered. The street dogs aren't this hostile around this area. He wasn't even sure this many street dogs lived here.

Harry then heard clinking sounds, of chains being dragged on the ground, but Harry couldn't see anything.

It's coming towards us. Harry thought before pulling out his wand.

The clinking sounds grew louder as Harry raised his wand.

"Stupefy!" Harry yelled as the spell shot out and collided with the source of the clinking sounds.

Something growled as the air rippled and Harry and Dudley stifled a scream.

A giant black dog about the size of a bus stood behind the circle of street dogs. Its fur was shaggy and its fangs were stained red, with its canines being almost half of Harry's size. Its claws were too large to be a normal dog's and its eyes were blood red.

Staring at its eyes, Harry was assaulted by a number of visions.

Voldemort killing his parents…

Dumbledore looking at Professor Snape on the top of the astronomy tower…

Cedric's lifeless eyes…

Harry gasped as mocking laughter broke him out of his stupor.

"Would ya look at that, Barghest? The little sorcerer's already spooked." A nasal voice spoke as Harry noticed a tall humanoid made completely of wood standing beside the enormous dog, grinning at him.

Barghest let out a soft growl as the humanoid laughed. "Oh don't be so serious. What can one little human sorcerer and his poor mortal friend do to us? Look at him, he's already pissed himself!" The humanoid spoke laughing as Harry noticed Dudley's pants were wet, Dudley staring with wide eyes as his body was paralysed.

"Dudley, snap out of it." Harry spoke warily as the humanoid shook his head.

"He's probably having a fun time looking at his pathetic life within dear Barghest's eyes…" The humanoid spoke as Harry tentatively raised his wand.

"Who are you?" He asked.

"I'm Spriggan, little Potter." The humanoid replied. "Well, it's not really my name…but that's how it works among our kind."

"Your kind? You work for Voldemort?" Harry asked as Barghest let out a loud growl that rattled Harry's bones.

"Sh!" Spriggan spoke. "Don't say that particular individual's name in front of Barghest. He does not like those who escape death." Spriggan spoke before vines erupted out of nowhere and wrapped around Harry's arm, dragging him to the ground.

"Harry!" Dudley exclaimed as Spriggan walked upto Harry and kneeled down next to him. "Anyways, it is rather disappointing that the so-called Dark Lord struggles against the likes of you."

Harry stared at Spriggan defiantly.

I need to get Dudley out of here. He thought.

"Ooh, is that a little bit of bravado I'm sensing? Good, you're exactly like all those hare-brained heroes who have come to our lands over the years, hoping that their miserable lives would have some value through their stupidity…I mean, courage." Spriggan spoke as Harry angled his wand down.

"H-Harry…" Harry heard Dudley whimper.

Barghest growled again as Spriggan looked at it. "Come on, Barghest! Just a little bit more fun, and then I can stick a branch through his mouth."

"Try it." Harry spoke with a glare.

Spriggan looked back at Harry with a sigh. "You need to work on your hero complex, boy. You think defeating one weak sorcerer, a teensy weensy snake and a bunch of angry spirits makes you some sort of omnipotent hero who can overcome anything?" Spriggan asked chuckling before scowling.

"Barghest can bite you in half before you can even finish a spe…"

"Bombarda!" Harry yelled as Spriggan was blown back by an explosion. The street dogs were blown back as Harry got up.

"DUDLEY! RUN BACK TO YOUR HOUSE!" He yelled as Dudley stared at him. "I'll hold them off! Now run, you bloody idiot!" Harry snapped as Dudley immediately scampered off as he turned back to Spriggan, who had a wooden bow in his hands and nocked an arrow aimed at Dudley.

No! Harry thought, raising his wand.

"Expelliarmus!" He spoke, knocking Spriggan's bow off his hands.

Before he could cast another spell, a dog bit at his wand as Harry struggled against it.

"Let it go!" He spoke but kicked the dog away before looking at Barghest.

Maybe its like a Dementor. Its aura feels similar. Harry thought before raising his wand.

"Expecto Patronum!" Harry spoke as the Patronus spirit flew out of his wand and slammed into Barghest.

But instead of being warded away, Barghest growled in irritation as a pit of dread formed in Harry's stomach.

It didn't hurt him. Harry thought before Barghest stared at him and its eyes glowed.

Harry immediately found himself looking at the corpses of Ron, Hermione, Sirius and so many more.

Harry's breath quickened as his eyes widened.

This isn't real. Harry thought raising his wand.

DEATHDEATHDEATHDEATHDEATHDEATHDEATHDEATHDEATHDEATHDEATH…A cacophony of voices sounded in his mind as Harry shook his head and closed his eyes.

"STOP IT!" He yelled, clutching his head as the voices continued to ring in his mind.

Pain suddenly exploded on his chest as Harry fell back, finding himself on the ground, looking at Barghest and Spriggan.

"Barghest! Did you have ruin the fun!" Spriggan snapped as Barghest stared at him before suddenly perking up.

Spriggan tilted his head. "You sense something?" He asked as Barghest growled.

"Oberon's beard! Since when were there Einherjar patrolling this area?!" Spriggan hissed.

Einherjar? Harry's delirious mind thought as he groaned in pain, his chest feeling like it was swimming in lava.

"They're here somewhere!" Harry heard someone exclaim in the distance as Spriggan shook his head and looked back at Harry.

"Let's go, Barghest. I don't want to fight those Nordic zombies here in England." Spriggan spoke, before looking at Harry. "We'll take care of him later." He spoke as Harry noticed Barghest's left paw dripping in blood.

Harry looked down to see three huge claw marks across his chest, blood flowing. Harry could taste iron as blood flowed out of his mouth.

"Until we meet again, little Potter." Spriggan spoke. "That is…if you can live long enough to receive help." He spoke before he and Barghest melted into the shadows.

"Magnus! I see someone!" Harry heard the same voice again.

"Help…" He spoke weakly as someone suddenly came up. Harry felt his vision going black as two people came up to him.

"Shit, they got to a kid." He noticed one of them speak. "Magnus, his injuries."

Harry was then rolled onto his back and looked at the two people. Both were wearing black coats. One was an adult man with wild brown hair and another was much younger with longer blonde hair and grey eyes staring at him in concern.

Harry noticed a third person with pale skin, white hair and…pointy ears?

An Elf? Harry thought in confusion before he lost consciousness.

Magnus Chase's day was already off to a great start. It all began when Odin had ordered a large chunk of Einherjar be sent to Asgard's territory all over the world to curb increasing Jötnar activity because of the mysterious fog that had blanketed the world, and Magnus and Halfborn were part of the group that would be operating in England.

Why in England? Most of the Einherjar being sent there were all part of the numerous expeditions to England back in the 7th and 8th centuries since they were already familiar with the terrain, which of course included Halfborn. And Magnus was being sent off because of his healing skills, while he took Hearth for any magical threats.

Here in England, Magnus, Halfborn and Hearth also discovered there was the added problem of Fairies (Who were apparently not the cute fuzzy tinker bell creatures that Magnus thought of) who were making things difficult for the Einherjar, always sneaking Jötnar into the cities and disrupting the activities of Einherjar. So, they'd been on the lookout for any fairies in London.

Just some time back, Hearth's runes alerted them to the presence of two powerful fairies appearing in Privet Drive and the three set out to subdue them.

And coming onto the scene, the fairies had escaped, leaving behind a bleeding boy with claw marks on his chest.

He has magic. Hearth signed as Magnus stared at him.

"A mortal having…magic?"

"He's probably a wizard." Halfborn grunted. "Back when I was alive, I did spot some strange people with sticks performing sorcery moving about in Mercia.

"Wizards...as in wand waving and all that?" Magnus asked. Well, he guessed he learnt some weird thing or the other everyday in Britain.

Halfborn nodded. "Now Magnus, no questions and heal him before he dies of Blood loss."

Magnus nodded and pressed his hand against the unconscious boy's chest, drawing upon his power. Magnus immediately noticed something trying to keep the wound open.

Did that Fairy cast some magic? Magnus thought annoyed as he grit his teeth, pushing against the foreign magic to close up the boy's wounds as sweat formed on his forehead.

Soon, with a lot of struggle, Magnus managed to close them, although three jagged scars remained.

"Alright, now where is this kid's house?" Halfborn spoke as Magnus shook his head.

He lost consciousness before we could ask him. Hearth signed.

"Then let's ask someone." Magnus spoke before they noticed an old woman staring at them with wide eyes.

"Do you know this boy, ma'am?" Magnus asked as the woman walked up.

"My goodness, he's alright! If those monsters had killed him…"

"Monsters?" Magnus asked as the woman stared at them with discomfort.

"We work with the ministry of magic." Halfborn spoke as Magnus spotted Hearth using a rune.

"Oh…well, there was a massive black dog with red eyes and some sort of huge Bowtruckle."

Magnus looked at Halfborn and Hearth.

Well, we have a lead to our fairies. Magnus thought.

"Will he be alright?" The woman asked as Magnus nodded. "I've closed up his wounds, btu there's still a nasty scar. Also, Ma'am, could you tell where his house is?"

"Of course…I-I'll show you." The woman replied as Halfborn picked up Harry's body, taking them to the house. There, some family stared at them as they entered. Before anyone could ask questions, Halfborn plopped the boy down on the couch, Magnus quickly thanked the woman before Hearth distorted their memories with his runes to forget about them.

Coming out, Halfborn shook his head. "The Fairies are really becoming a pain in the arse." He spoke as Magnus frowned. It was much easier to deal with the Jotnar because they usually came up in their faces to smash them into a pulp. The Fairies? They were sneaky, always trying to avoid a fight with the Einherjar. And after reports of Einherjar defeating a large group of fairies despite being outnumbered by them, Magnus could see why.

They can't beat us head-on, so they go behind our backs. He thought.

"The problem can only end if we head to Scotland." Magnus spoke as Halfborn shook his head.

"Odin has given explicit orders not to venture north of the borders of Old Northumbria. The Fairies have the advantage of home territory once we cross Hadrian's wall. Besides, we really can't leave behind the problem of the Jötnar. It's only a matter of time before they start spilling over into Lundenburg."

"Lundenburg?" Magnus asked.

London. Hearth signed as Magnus nodded in understanding.

"But then, we still need to do something about the fairies, not to mention that the fog itself is coming from the northern parts of Britain." Halfborn spoke as Magnus sighed. "Should we call for extra help?"

"We can't call in more Einherjar now."

"Not Einherjar. Outside help."

Halfborn frowned before his eyes widened in realization. "...Last time you met, she didn't seem like wanting to get this quest business again."

"Well, it's affecting everybody in the western hemisphere, not just us. The increased presence of monsters is disrupting life for everyone, including Annabeth's." Magnus spoke. "I'll send a raven to Annabeth. If she accepts, which I'm hoping she does, then we won't have to worry about the Fairy problem."

"And if she doesn't?"

"Uh…"

"Well, we'll cross that bridge when it comes." Halfborn grunted. "Come on, let's go back to our hotel." He spoke as the three walked off.

A/N: Alright, I discovered that Rowan's Shade and Soulless Plains are both eating at my head, because I love incorporating mythology into my stories, something that I haven't been able to do much of in Rowan's Shade because its too early and Fate's mythological depictions just don't feel right to me. So, to calm my mind, I'm starting another story beside Rowan's Shade which can have me go ham with the myth and history stuff. And surprisingly, its a Harry Potter crossover, something that I never imagined I would write.

I don't like Harry Potter, and I have no idea how, but I got attached to Harry Potter. Well, more like, PJO/HP crossovers. I think I still don't like any Harry Potter media outside of this. So, while browsing through the crossovers, I picked up mostly the 'demigods go to hogwarts' crossovers, which are either just demigods having fun in Hogwarts or just some mythical villain and Voldemort teaming up, which is fine. This story is anyway falling in the second category, because I wanted to try my hand at this type and just slap in my own stuff.

So, for the people who mostly stay in the Harry Potter fandom or those who are seeing my work for the first time: I'm Hsuyaa. I've been active in the PJO, RWBY and Fate fandoms and this is me entering the HP fandom. Just to warn you, my knowledge of Harry Potter comes from fanfics, wikis and the films. So sorry if something in this story clashes with the books, because I've not read them and I don't have the will to do so.

I chose fairies, because I realize British folklore is really underrated. FGO LB6 really opened my mind to Fairy Lore and that Fairies are a lot more complicated than the Tinker Bell look-alikes we usually see in media. Yes, I know some of the British folklore creatures are incorporated into Harry Potter, but I tend not to follow the source material to the tee and always write my own storylines and lore, because I realise I'm a lot more comfortable with that. Plus, Lots and Lots of Celtic mythology in this.

No Percy Jackson this chapter, he'll appear in the next one.

Magnus Chase is not a major character in this story, he and his crew will just be minor characters appearing from time to time. Main focus is still on Percy's and Harry's crew.

I'll be alternating between this and Rowan's Shade. And be warned, I'm still going to face difficulty in squeezing out chapters until March ends. So, you might not expect a quick update on this story as well.

Hope you guys enjoyed and constructive criticism is appreciated!

Foot notes:

Barghest: Demonic hound from Yorkshire that was either present at someone's death, or foretelling the death of someone in the future. It sometimes appears in funeral processions and getting in its way is a bad idea. It's a malevolent creature through and through, nothing like any black dogs which guard cemeteries. It is said it causes wounds that can't heal, which I'm not following and have based it on the assumption that wounds caused by a Barghest can't be healed by normal means. The glowey eyes part is something I made up because of Barghest's heavy association with Death.

Spriggan: Spriggans are fairies from Cornwall who were mischievous and loved playing tricks on humans, such destroying houses with strong winds, ruining crops, kidnapping children and replacing them with Changelings (Another type of Fairy) etc. Look, I saw some really cool spriggan art on the web and based the Spriggan in this chapter off that.