Hello everybody! This will be a GOT/Merlin crossover, though you don't need to see Merlin to understand this story because it will follow GOT, not Merlin.

In this story Morgana is the only legitimate daughter of Robert Baratheon.

Her mother is a Targaryen. I've read on Wikipedia that Rhaella – Aerys's wife – had numerous miscarriages between Rhaegar and Viserys. Well, one of those miscarriages wasn't actually a miscarriage in this story. Daena Targaryen – Morgana's mother – is born in 263 AC (After Conquest). She was supposed to marry Rhaegar but she sleeps with Robert and she becomes pregnant therefore they marry. Morgana is born in 281 AC – a few months before the Tourney of Harrenhal – and her mother dies in childbirth. Robert is therefore free to marry Lyanna. Of course then the Tourney happens and then Robert's Rebellion.

Arthur, on the other hand, is Robert Baratheon's nephew. Uther Baratheon was Robert and Stannis's older brother and Arthur is his son. Uther died one year before Robert's Rebellion, of fever. No Renly Baratheon in this story, he doesn't exist here.

Arthur is 21 years old when the story begins while Morgana is 17.

I only watch the TV show, I didn't read the books so this story will follow the TV Show. I know some stuff about the books – like the 'three heads of the dragon' prophecy (hence the title) – but in general I only care about what happens in the TV Show. This means that characters present in the books like Aegon, Arianne Martell, Willas Tyrell etc won't appear in this story. This means that Olenna Tyrell has only one grandson and one granddaughter (Loras and Margery) and that Prince Dorian has only one son – Trystan.

No Magic beside the supernatural elements present in 'Game of Thrones'. Though Morgana will have prophetic dreams like in 'Merlin'.

Pairings:Morgana/Arthur(incest between first cousins), Morgana/Robb but neither of these will be the final pairing (the other couples are Canon). Oh, and Merlin/Mithian too, though it will be a background couple. For the final pairings I've decided on Jaime/Morgana (because I love Jaime) and Jon/Daenerys and probably Tyrion/Sansa too.

Warnings: INCEST! But it's Game of Thrones so I don't really care. Violence, gore etc like Canon, though I'll avoid being too graphic.

Hope you like it! Tell me what you think!

Prologue

298 AC - King's Landing

Morgana moaned slightly when Arthur licked a particularly sensitive spot behind her ear. She passed her hands through his hair, encouraging his movements, thrusting her hips upwards towards his, increasing the friction of their bodies and bringing the both of them closer to complexion.

She loved feeling his body on top of her, warm and sweaty, his hard member between her folds, rubbing against her. She brought his mouth to hers, kissing him passionately, tongues battling against each other. She was so close, just a few more seconds and she felt pleasure invading her senses, Arthur reaching his peak soon after, spurting warm semen over her abdomen and between her legs.

She closed her eyes in ecstasy, trying not to scream too much in case someone passing in front of Arthur's door could hear her.

Their relationship wasn't as forbidden as that of Sir Jaime and Queen Cersei but she was sure her father would never approve. They were cousins and marriage between cousins was pretty common but she knew Robert Baratheon had some different union in mind for her that his nephew. If he found out that Morgana wasn't as innocent and untouched as he thought her to be, there will be dire consequences for the both of them. They were careful though, very careful and she had no intention to be found out if she had anything to say about it.

And talking about Jaime and Cersei, she had found out about the two siblings by chance, one night she couldn't sleep, she had been wandering the castle when she found them kissing against a dark alcove. She was no more than eight namedays at the time and since then she had kept their secret, the secret they had no idea she knew. They hadn't been exactly cautious in hiding their relationship however because Jon Arryn, the King's Hand, had found out about them and threatened to tell the King. Of course he didn't live long past that threat, as it usually happened when someone threatened Cersei. Still, that had been one more person to found out their secret and Morgana sometimes wondered how much time would pass before it became common knowledge.

Of course, she had no intention of telling anyone that the Queen had a long standing relationship with her brother. She wasn't stupid, Cersei was too dangerous and unpredictable for her to face alone and she wasn't sure that without proof her father would believe her.

Not that she really blamed Cersei for finding solace in someone else's arms. Her father wasn't exactly a good husband – or a good king for that matter.

"Hey, where did you go?" Arthur's voice brought her back to the present and she smiled at him in apology.

"Sorry, I was just worried someone might have heard us!" She explained, only half lying.

Arthur kissed her sweetly before moving from on top of her. "Don't worry, they didn't notice anything since we started doing this two years ago, I don't see why they would suddenly notice now".

"You're right, of course!" She smiled before kissing him again urgently.

"You never have enough, have you?" Arthur asked between kisses.

"Are you complaining?" She asked with a flirtatious look.

"Never!" He replied with lust in his eyes, then becoming serious again, he continued "I just wish…"

Morgana frowned slightly, knowing exactly what he was going to say. It wasn't the first time they had that discussion. "I know, but we can't. I have to stay a maiden until my wedding day and beside, it's not like we didn't have lots of fun doing everything beside that!"

"I know but it's not the same. I want to know what is like being inside you and the idea of someone else having you when I can't…" He made a face that was a mixture of anger and deep pain.

"Do you think I want to be married to some Lord I've never met? Someone that will probably just use me for his pleasure and to produce an heir before fucking every whore and kitchen wench in the near vicinity like the King does?" She couldn't help but show her irritation at his words.

"I'm sorry, I didn't mean it like that," Arthur said immediately in a contrite voice. "It's just…I love you Morgana, I've always loved you and the idea that we'll have to marry one day and be separated from each other, that we can never be together in the light of day…it kills me…"

Morgana kissed him again before saying "I love you too, always have, always will. But we have to accept what we can't change and relish in the moments we have together! We knew from the beginning that we could never be more than what we are now."

"What if I asked your father for your hand? I'm the Lord of the Stormlands after all. Ours would be a good match. Why would your father refuse?" Arthur said, a little whiny.

"You know why. My father may be king but we both know the Lannisters are the one with the real power. My father wants to marry me off to some Lord of one of the big Houses so that he can regain some of that power back. The same will happen to you. Trystane Martell is too young for me, same with Robert Arryn but Robb Stark and Loras Tyrell would both be good matches for me and I'm sure father has already thought about it. However if he married me off with Robb Stark and you with Margery Tyrell he will have the alliances of two great houses in one fell swoop. I'm just waiting for the day he will finally announce the match, it's almost inevitable."

Arthur sighed "I know". Then with a small smirk he asked her "Why must you be so reasonable all the time?"

Morgana smirked back at him "One of us must!"

Half an hour later, when Morgana had returned to her room, had bathed and had a maid help her dress, she was about to sit down to have breakfast when she heard a knock on her door.

"Come in!" She called out. The door opened and in came Ser Jaime Lannister.

"My Princess, the King requires your presence in his chambers. He has urgent matters to discuss with you."

Morgana sighed before answering "Tell the King I will be along shortly"

"The King said I have to escort you there immediately"

'And we can never disobey the King…' "Very well." She chanced a look in the mirror to make sure she was presentable. Not that it mattered anyway. Her father noticed her only if he needed to order her to do something or if he had something to complain about, which happened rarely since she usually behaved like the perfect Princess who always does as she was told to. Or at least that was what she wanted her father to think. In reality, she simply did as she wanted but made sure not to get caught.

That was how she had learned how to use a sword even if her father had been adamant that it was not ladylike behaviour. It had been Arthur that had taught her how since she was nine name days. Now, almost eight years later, she was proud to say that she could beat even him sometimes - the second best swordsman in the seven Kingdoms after Jaime - not that Arthur would ever admit it.

"Lead the way, Ser Jaime" She said in the end to the knight at her side. Ser Jaime took her arm in his before escorting her out of the room.

Morgana couldn't help the slight tremor in her hands at coming face to face with her father. They usually avoid being in the same room alone. Robert could barely stand the sight of her most of the times. Sometimes Robert's looks towards her made her afraid for her life – though Robert had never tried to hurt her. She knew that her father didn't love her. She was a useful tool to him – a princess ready to be married off to some Great Lord and make alliances, nothing more.

She was lucky that he hadn't decided to kill her like what happened to Rhaegar Targaryen's children. Her father's deep seethed hatred towards everything Targaryen extended towards her too, though not to the same extent as the two Targaryens across the narrow sea. Morgana thought that the only reason why they were still alive was because Robert was too lazy to try to do something about it. Though, there had been some murder attempts during the years anyway.

Fortunately the fact that she was Robert's daughter – the black hair on her head was proof of that – had saved her from a horrible death when the Rebellion was over. If her mother had survive Morgana's birth she was sure Robert would have killed her himself just so he could marry Lyanna Stark. From what she heard he had been obsessed with her and even now, it was always about Lyanna – though she was sure that if he had been able to marry her he wouldn't have stopped sleeping around.

Robert had been forced to marry Daena Targaryen – that was her mother's name – after the two of them had slept together and Daena had become pregnant. When everyone had found out about the whole affair, it had created a big scandal because Daena was supposed to marry Rhaegar and instead she had been forced to marry Robert to salvage her reputation.

Ironic how her name had been Daena, because she too had defied her family just like Daena the Defiant. Not for love, no. From what Morgana understood, her mother slept with Robert because she didn't want to marry her brother and Rhaegar didn't want to marry her. Of course Robert Baratheon was a terrible husband so maybe it would have been better if her mother had married Rhaegar instead. Maybe the rebellion wouldn't have happened if she did.

Morgana returned to reality when she realized that she and Ser Jaime were standing in front of her father's chambers. Ser Jaime knocked on the door and waited for a servant to open it.

"Ah, Kingslayer!" Her father said to Jaime and Morgana immediately noticed the tick in his jaw that always appeared whenever he was called that. Morgana hated the hypocrisy of it all. Everyone had been happy when Jaime had killed the Mad King but everyone hated Jaime for killing him. Sure, Ser Jaime had gone against his vows but Aerys Targaryen was called the Mad King for a reason, he burned people for amusement. He had deserved to die and Morgana was sure that Ser Jaime had had a good reason for killing him, though he had never explained himself, never tried to defend himself.

"You brought her to me." The King continued. He looked at her with a smile and Morgana was immediately suspicious. Her father smiled to her only when he wanted her to do something. "Come Morgana, we have much to discuss."

He turned around without even looking at her and Morgana looked at Jaime taking his place in front of the door before closing it behind her.

"Sit child." His father said to her, indicating one of the two chairs around the table filled to the brim with food and wine. "Have you break your fast yet?"

"No father," she replied demurely, sitting down in a fluid move before biting on an apple.

"I'm sure you are aware that I intend to ask Ned Stark to substitute Jon Arryn as my new Hand and that's why we are leaving for Winterfell in a few days."

"Yes father," Morgana replied unnecessarily since his was more of a rhetorical question than anything.

"Did you know that Ned has a son close to you in age?"

A feeling of dread assailed her at those words. The time had finally come, it seemed.

The King continued talking, not really expecting a reply. "His name is Robb. I've heard he's a fine lad, handsome, honest, kind, honourable. It would be a most favourable match. The Starks are a very important and powerful House and Robb is the heir to Winterfell. You would become the Lady of Winterfell one day." Robert explained calmly.

"I understand, father." Morgana merely said in reply. She knew protesting would be pointless. Her father expected her to do as she was told, like usual. The King wanted her to marry Robb Stark – someone she had never met – and she had no other choice but do as he wanted. What the King wanted, the King would get. After all she had known all along that this day would come sooner or later, she was just hoping later rather than sooner.

"Of course, I will have to talk to Ned before making things official, though I don't see why he wouldn't agree."

"Yes, father." Morgana said tonelessly. "May I be excused?"

"Of course." Her father nodded his consent and Morgana got up from the chair she was sitting on. She opened the door and left the room without looking back. She could feel Sir Jaime's gaze on her – he had probably heard what her and the King had discussed – but she didn't turn to look at him. She instead continued walking in the direction of her room. She needed to talk to Arthur immediately.