Disclaimer: I don't own Merlin or Harry Potter!

Author's Note: This is my take on a Merlin X Harry Potter crossover boggart! Scene. Enjoy~!

The Warlock's Broken Heart

It was during one of the many times in which Merlin masqueraded as a Hogwarts student that he first encountered the creature of his worst nightmares. Despite all the travelling he has done over the past millennia, the Warlock had never once faced off against a Boggart. Yes, he had heard of them, he could even sense them hiding in their temporary abodes and as a result he went to great lengths to avoid the dreaded creatures.

He had enough of it haunting him in his sleep every night, Merlin didn't wish to see his fear materialize right in front of him while he was awake too.

"Now repeat after me: Riddikulus!" Professor Lupin instructed.

Of all the times he had stayed at Hogwarts, never once had there been a practical lesson with a Boggart in a Defence Against the Dark Arts class. Then again they were going through an alarming amount of DADA professors at the moment; it shouldn't surprise him that some changes to the curriculum had been made as well. That didn't mean he had to like it.

"Fred Weasley," the professor's voice cut through his thoughts and a ginger-haired teenage boy stepped up to face his fear.

What would he do if the Boggart exposed him?

How would he be able to face it in front of all these people? It wasn't as if he wasn't capable of handling a Boggart, Merlin would rather face it somewhere away from prying eyes.

Facing a Boggart would mean he would see-

"Mervin Emyr," Professor Lupin announced his alias, snapping the Warlock-in-disguise out of his thoughts. Seeing his student's pale face, he added: "Don't worry, Mervin. You'll be fine,"

The class of fifth years watched curiously as Merlin took a shaky stepped towards his opponent. They didn't know much about him and were keen to find out more. Merlin on the other hand was not so keen. Sure, he had faced worse in the past which was everything from Serkets and Dorocha to every single war mankind has fought since. Boggarts were different. They took on the form of your worst fears, Serkets certainly do not. Even the strongest of wizards may crumble at the sight of the form their Boggart would take.

He stood before the magical creature and its body began to shift through various shapes which flashed by in a blur. Merlin briefly wondered if it, like many creatures of magic, could sense he is Emrys. However, like the Dorocha, the Boggart ignored whatever it may have sensed to settle on its final form. His breath hitched at the sight.

"Arthur…" Merlin whispered, tears gathering in the corners of his eyes as he took in every detail of his long dead best friend. He looked the same as when he last saw him. Merlin watched helplessly as a scene from his very nightmares, an old memory which haunted him daily, was replayed before his and the class' eyes.

Mordred stabbing Arthur with a blade forged in a dragon's breath. Arthur's startled look before he collapsed. Blood. Blood leaking from the mortal wound in the King's chest.

Someone in the back of the class screamed.

It all felt too real. He knew it was nothing but a recreation of his fears, yet he couldn't help but feel that same desperation to saves his best friend's life. To not let it happen again. He couldn't fail Arthur again. He needs to save him!

"ARTHUR!" His heart-wrenching cry tore through the silent classroom, startling the students and professor. Merlin tried to run to his King's side. He tried but the Boggart wouldn't let him. "No! I can't let this happen again! Please! Let me heal him! Arthur!"

His audience watched as a river of tears streamed down the dark-haired boy's face as he attempted to reach the blonde-haired man.

The cruel Boggart would not even allow the Warlock to touch Arthur, forcing him to watch the one person he most cared about die, so that he couldn't do anything to stop it. Just like back then.

"Arthur!" Merlin called desperately yet again and surprisingly found himself able to move closer. The moment he realised this, the Warlock sprinted to his King's side, wrapping his arms around Arthur and pulling him as close as possible to himself. It was a scene not unlike the one from his past.

Up close, Merlin was able to smell Arthur's familiar scent, just as he remembered it, mixed with the smell of death and the coppery tang of blood. The Boggart Arthur stared up at Merlin with glassy-blue eyes as he reached up with one hand to ruffle Merlin's hair in a perfect re-creation of the memory. For days after Arthur's death, Merlin could feel the lingering touch of his hand. Thousands of years later he could still feel his warmth in his dreams.

"Arth-ur…" Merlin's fragmented whisper hung in the air.

Arthur's hand fell limp and his eyelids slowly slid shut.

"Arthur! Arthur! Arthur! NO!" On the last word his voice cracked and his eyes shone golden, glittering with tears. The Boggart was engulfed in a glow that matched the colour his eyes were now, blazing with a powerful ancient magic.

His audience squeezed their eyes closed as the flashed nearly blinded them. Once they had finished blinking the spots away from their vision they were shocked to discover the Boggart disintegrating into a fine sparkling powder before completely fading away. This student had destroyed a Boggart! Something that was supposed to be impossible!

Merlin was left kneeling on the classroom floor, sobs wracking his thin frame.

His identity hadn't been revealed, but his worst memory had.

Merlin wasn't sure if that made it any better. It made him wish it had gone and exposed him instead. Anything to prevent him from feeling as though his heart was ripped out and torn to shreds.

Once again he would carefully try and patch the pieces back together.

Once again he would find himself comforted by others.

Back then it had been Gaius, Gwen and the Knights. Now it was his classmates and professors.

Merlin was glad he always had his friends to support him. Even at Hogwarts, despite these people not knowing who he truly was, they helped him mend his broken heart.

Author's Note:

What did you think of it? I'd love to know. Thanks for reading everyone! :D

I've read quite a lot of crossovers in this section and I've decided to use a more unique alias for Merlin to use. Since I've been seeing a lot of Myrddin and Martin, etc. I don't think anyone has come up with Mervin yet, I'm not sure but I definitely know no-one has come up with Emyr (Welsh for "King"-and it looks like Emrys) for his surname.

So, if any of you happen to be readers of my Don't Be Lonely story, well…yes I know I'm supposed to be writing that but yeah my mind has been on Merlin a lot lately. It's gotten to the point I've nearly finished another Merlin/Harry crossover (which is longer than this one and I actually wrote that one first), and about 3 Merlin fics on the way. One of them is actually already finished but I wanted to edit it a bit more until I'm happy with it.

Sooooooo, yeah. Oh! Don't despair for I'm not going to abandon it or anything, I'm determined to get it finished. It's nearly there anyway. :)

On a different note, did any of you get the reference in the title? ;) It's like a mix of the two fandoms!

Until next time~!