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Crossover challenge/ideas

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Challenge 1: One Piece/Harry Potter

Relationship: Portgas D. Ace/Fem!Harry Potter

Premise: Female Harry Potter just survived the war and is supremely done with the Magical World's BS. She is somehow transported to the One Piece World where she makes the impact on the world that a "D" would.

-Female Harry has to be strong (must be able to fight and hold her own on a physical level, not just through dependence on magic; must be intelligent)
-Luna needs to have provided some sort of cryptic Luna-esque advice about travels, meeting someone important, finding happiness, etc
-Ace must live due to Harry's intervention
-Seastone must not affect Harry's abilities
-Must have scars from the war (physical or psychological, or both, but nothing like amputation or such; cannot have just escaped everything unscathed)
-must be able to swim (and know the bubble head charm) - she will end up in a world of water, enough said

-Sirius alive in One piece world (possibly living as a dog)
-Harry having an animagus form
-Harry being able to use Haki (possibly having Conqueror's Haki that has been used in the Final Battle)
-Harry meeting Ace for the first time at Impel Down
-Fem Harry can have hidden her intelligence/physical fighting or training by finding the room of requirements earlier in her schooling

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Magical Tides

By: Simple Memories

Portgas D. Ace/Hariel D. Potter




Hariel “Harry” Dorea Potter sighed as she sat in her cell at Impel Down, emerald green eyes taking first looking at the useless seastone chains around her wrists, then taking in the dank, gray walls, smirking slightly as she contemplated how she came to be here, and why she had decided to stay in this cell. How was she supposed to know that the ship she blew up with a well placed Bombarda was a high level marine ship; all she knew was: they were attacking the island town she had landed in, and she could do something about it. Hariel had won the wizarding war, but it took its toll on her. At only 18 years old, she was bone tired and held more than her fair share of scars, though that did not mean she would stand by and do nothing. 

Sighing again, Harry leaned her head back and closed her eyes.

I wonder where Luna is right now she thought, knowing that the blonde had left her to go explore a bit more, allowing her sight to guide her. Their first conversation on meeting, way back when she was only 12 years old still rings clearly in her head:


“You were born with a will of D, though you ended up in the wrong place.” 

Hariel startled slightly at the sudden light voice interrupted her contemplation on the way back to Hogwarts. Turning towards the compartment door, she saw a small, blonde girl wearing radish earrings, her light blue/gray eyes focused on Harry with an intense stare, though seeming to be somewhat hazy.

“Excuse me?” Hariel stated, somewhat flustered, “What exactly do you mean by that?”

“Oh, I guess the nargles haven’t been talking to you as much as they seem to be, huh?” responded the blonde, her airy voice slightly distant.

“Who are you?”

“Luna Lovegood, and you are Hariel D. Potter, the one whose happiness starts at Impel Down, and whose destiny is with the Ace of Fire.” replied Luna.

*******End FLASHBACK*****

That had been the start of their friendship, with Hariel finding every time Luna took the time to actually say something, it always ended up true. Luna was the reason Harry had even gotten to this world, it was her words which convinced Harry to allow herself to be “caught” and brought to Impel Down in the first place, while Luna left to continue to explore the world on the outside.

After all, sometimes prisons were the best place to gather information about the world, and its not like they could take her weapons, for those Marine’s couldn’t perceive them due to the Notice Me Not charms on all of her stuff attached to her, as well as their belief that she was being drained by the seastone chains.

Hariel crossed her legs, looking down at her rather comfortable heat regulating dragon hide pants and boots, small amounts of blood spattered at the pant hem, checking to ensure that all of her pouches holding potions, weapons, and food were attached where they were supposed to be. She had been here 2 weeks already, and learned much about how this world worked and why they thought these silly chains would keep her submissive.

Apparently, these Marines thought she had eaten a “Devil’s Fruit” of some kind which allowed her to blow up the ship from afar, and that she therefore would have all of the weaknesses associated with it, such as being drained by seastone and being unable to swim. She snorted softly at that thought, as if they could separate her from her magic. Not to toot her own horn, but Hariel was proficient at wandless magic, more out of necessity than anything else, but still, her magic was much too strong for these people to separate from her.

Unknown to her captors, she had gotten herself out of this cell and explored the entirety of Impel Down within the last two weeks, meeting with other prisoners and finding out information on Pirates (which for some reason the Marines thought she was, hence the bounty on her head), the World Government, and the Revolutionaries.

Thinking about it, talking with Ivankov had provided the most information, though he did not understand why she stayed when it was obvious that the Marines really couldn’t hold her.


“Why aren’t you trying to escape?” Ivankov asked the third time she came to him to ask questions, looking at her dark hair, tousled like she had just gotten out of bed, slightly chapped lips, and ripped shirt barely hiding the bruises and mild cuts that come from the Warden trying to break someone. He knew this woman in front of him had a different agenda. She was strong and was able to get out of the cuffs and cells, as demonstrated by her presence on his level.

“Why would I leave now?” she replied, her voice soft and husky, a small smile fluttering at the edges of her mouth, green eyes alight with mischief, “I haven’t gotten what I came for yet.”

*******END OF FLASHBACK*******

She was waiting, anticipation seeping down her spine as her magic started to churn within her breast, telling her that the time Luna had warned her of was coming. 

She looked up as a door opened at the end of the cell rows, peering out as the Marines dragged a tall man chained in seastone cuffs, towards her cell.

Goon 1 as she privately thought of him, his name not being important enough for her to remember, leered at her as he, to her surprise, unlocked her cell door.

“Got ya a roommate, bitch.” He laughed as he motioned for the other two to bring the man into her cell and chain him to the opposite wall.

She stayed quiet, allowing the guard’s words to fade into the background, as her sharp eyes took in all the details of not only the guards, but the man they had just chained opposite her. The guards’ uniforms were unsullied, but there was blood dripping from the back of the man’s head, which was hanging down as if asleep, with bruises and small lacerations decorating what she could see of his chest and arms, which considering his shirtless state, was quite a bit. Still, she held her tongue, ignoring the guard that had continued to taunt her and the new prisoner, for she knew how to fade into the background, to prevent extra attention to be paid to her, not responding being one of the key ingredients to her easy survival here.

Seeing that she wasn’t responding to the taunts he was giving, the blonde marine sniffed and turned, motioning for his two guards to follow him out of the cell.

“We’ll see if you get fed today,” his high, nasally voice called over his shoulder, “after all, the dead don’t need to eat.” He laughed here, as if he had made the best joke ever. 

Silently, she listened to his footsteps retreat, sharp green eyes following him out of the cell block before returning her gaze to her new cellmate, studying as he seemed to jolt awake. Black eyes raised to striking green, shock slackening his freckled face as he recognized that he wasn’t alone in the cell.

“Nice to meet you,” Hariel stated, green eyes glowing with mirth and sparking with mischief, “I’m Hariel, apparently your new cellmate.” Her magic was moving restlessly underneath her skin, waiting for the reply.

He stared at her for a long moment. Taking in her ripped shirt, showing off fading bruises and healing cuts, undamaged pants, and to his surprise, pouches and what looked like weapons still attached to her belt, seastone chains wrapping her wrists.

“Portgas D. Ace,” He replied, his voice low and smooth, “How do you still have your stuff?” Her magic sung, and a grin made its way across her face, playfulness shining in her eyes. This was what she was waiting for.

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Challenge 2:

Female Harry Potter/Marco


Female Harry chooses to go on when struck by the killing curse during the final battle. She had died with a smile on her lips, knowing that the world would take care of Voldemort one way or another, and she was free. When she made that choice, having mastery over the hallows due to having been in possession or having allegiance of them all without actually wanting their power, Death approached her. In return for giving the Hallows back, since she (he? they?) could not take her soul at this time, he would allow her to keep her power and knowledge of her life and transfer her to a new world. When she died in this new world, though, she would actually go on to be with her family. She chooses to transfer to the new world. She is born, the first born Daughter of Portgas D. Rogue and Gol D. Roger, but her consciousness wakes when her mother is giving birth to her baby brother, Ace. She is thought to be Ace’s half-sibling instead of full sibling, as she takes after her mother in looks except with striking green eyes. 

Must haves:

-Marco/Female Harry Potter pairing

-Harry must keep her magic secret successfully

-No devil fruit Harry

-Animagus form is a must

-She must be a pirate captain, with a large bounty (but no picture, only a description), and the Whitebeard crew must not make the connection between her and Ace until it is revealed to them

-Ace must live somehow due to her intervention during his Execution

-Harry must be able to go up against and Admiral and win (at least a significant portion of the time)



-Her keeping Ace’s heritage secret via magic in conjunction with Garp’s efforts

-She knows Shanks

-She teaches Ace and Luffy inherent types of magic or Haki (from teachings passed on by Rogue during her initial life with her)

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(Female Harry) grew up in a world where soul marks were the norm. Everyone was born with them, and there were a few facts that were known about them, common knowledge if you will. One, if both parties live, the mark will be colored, and if one died, the mark would turn grey, but not disappear. Two, the mark was always warm, because even if your match was dead, their soul always lived on to be reborn again.

(Female Harry) was the exception, not that she ever told anyone. Her mark, although it was colored, was always cold, and no research she had done allowed her to explain it.

Now that she has won the war, though she definitely will wear the scars of it, it is time for her to leave. Though her research could not explain why her mark was cold, it did allow her to find a ritual to bring her to her match, or at least to within a couple miles of her match.


Portgas D. Ace had had a cold, colorful mark on him for as long as he could remember, but no one else ever had one that he knew of. He had searched high and low for answers, becoming a Pirate not just to become Pirate King, but also in order to search further for answers to the strange cold mark that positively glowed with color. He had just about given up hope of having an answer when a girl with the most enchanting green eyes he had ever seen appears in his life. Could she have the answers?



-Harry must be an animagus

-She must be able to fight at least somewhat without magic

-She must have the ability to perform magic in the One Piece world, preferably wandless

-She must be able to create a way to allow Ace to use the unlocking spell be it via runes or an enchantment on something she gives him to wear

-Ace cannot be a Whitebeard Pirate when they meet for the first time


Thanks! :)

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Female Harry Potter

Pairing - any you want or none at all


The Wizarding war goes on MUCH longer than anyone thought it would, but (female Harry) finally ended it. She won, but lost so much more. She had accidentally collected all the Deathly Hallows, and lost her ability to die...or so it seemed. All her loved ones were dead, so she uses the stone, but not to call her dead loved ones; no, she uses it to call Death.

Death comes and Harry asks for them/it? to take back the Hallows, for their power is not supposed to be in the hands of mortals. It causes too much greed.

Death offers her a deal, as it can only truly take the Hallows back if their master is no longer in this world. Death will take the hallows and Harry can travel to a different world, live a different life, and die at the end of her life, as a normal mortal, as the Master or Death cannot actually die in the world where the title was gained. However there is a price for this travel. Because she is Death's master, she gets to choose the price, as a boon. She can either give up her current age, and start her life, with all the memories of her adult self in a child's body OR give up her magic. Harry chooses to give up her current age, as maybe with a child's body she can have the childhood she always was denied. (How old she ends up, is up to the author; she just needs to be older than Ace and Luffy)

She ends up on Goa Island as a child. Meets Ace and then Luffy and Sabo and helps to raise them, show them what love is, and teach them how to take care of themselves. 

It is assumed that she will change the story line. I am hoping that she sails off and becomes a pirate herself, highly infamous and very strong (due to her magic coming with her and her body adapting to be normal in the OP world). She can join any crew that the author chooses, or just be the captain of her own crew throughout.

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Female Harry had been in this strange world for about a year now, and she had learned much about the corrupt Government with the allowance of slaves, but only to the nobles, the so-called Celestial Dragons. She did well with adapting, staying under the radar, so to speak. 

She didn't know what the spell that Moldy-warts had hit her with right before the killing blow hit him, but it stranded her here for good.

She kept her head down and stayed out of everything until now. She couldn't stop herself from interfering. The stupid "noble" slob was attacking a chained child. The child was one such 'slave,' recently acquired from what she gathered. She knocked out the noble, killed his "guards" grabbed the child, and ran. 

Good thing her animagus form could fly and carry a child at the same time.


This was the story of how she got a bounty, one that ensured she became a pirate...