I do not own the DC Universe or characters, Harry Potter, or Percy Jackson book series or any Mythology

This can be a female Harry Potter or Dc character Mera takes Harry's place. The authors can choose which.

The Princess of Atlantis

I will be pushing the date of birth of Harry/Mera to 1987 along with all other Harry Potter characters in Harry's generation. It will be a requirement for the challenge.

Plot

Lily Potter has an affair with Poseidon; the author can decide on Lily's reasons as long as it's not Lily being charmed with magic or curse with magic, and drunk. I know that Lily Potter is not the type of person to do that but in my opinion given the right conditions, anyone is capable of doing things that is not in their character. The result in this affair is Lily becoming pregnant; Lily does not tell James so he thinks that the baby is his.

Lily tells James the truth a month before Mera is born. When the truth is out it results in a big argument which has Poseidon intervene. When Mera is, born Poseidon was there, because of the affair with James, Lily did not have many protectors so Voldemort got to her a lot easier. Mera does get the scar but it fades as she ages and Poseidon destroys the Horcrux that Voldemort puts on her. Mera is given to the Dursleys', She is treated the same as book canon Harry even though Petunia knows of Lily's affair she stills treats Mera horrible because of her past feelings of Lily. Petunia does not know the father of Mera but she does know that Gods are real.

When Mera is five, she goes on a cruise with the Dursleys' who had won it in a survey. It only allowed a family of four with two children being free so Mera was force to go. There was a terrorist incident on the ship that cause Mera fall overboard the ship and unknown to her being the only survivor.

Poseidon meets his daughter Mera, knowing that he cannot spend a lot of time he leaves one of his servants with Mera to teach Mera. Mera spends five years in the sea before going to the United States at the request of her father. In the U.S.A Mera meets a ten-year-old Luke Castellan where they both find out that the other is a Demi God.

Wizards' treatment & feelings toward Gods and Demi Gods: The Wizardry world know that Gods are real and worship the ones that govern over magic or in most cases, the Gods that they feel can give them benefit in worshipping them. Other Wizards hate the Gods or feel wariness over them. In the wizardry world, Demi Gods are treated in many different ways, in worship, in hatred, in jealousy, and in fear. Demi Gods born to a wizard do not need a wand to cast magic because of the god blood in the demi God they need no wand.

Demi Gods in Hogwarts or other schools: The author can make minor Harry Potter characters DemiGods but they cannot be children of the big Greek three like Mera. The author has the option to pick other mythology big Gods.

Mera's looks: Mera looks will model after the variant art by Stanley lau Mera Queen of Atlantis. With Lily's green eye color mix with a sea blue.

Mera's powers & Skills

Superhuman Strength: Mera has super strength that is equal to Hercules. Her strikes are like tidal waves crashing down.

Super Leaping: Mera can leap high and long distances like a fish leaping out of the sea.

Superhuman Durability: Mera is able to withstand the huge pressures of the deep ocean.

Enhanced Vision: Mera is able to see perfectly in the pitch-blackness of the deep ocean

Enhanced Hearing: Mera has developed this skill because of her time in the sea.

Superhuman Speed: Mera when she is in the Sea can move as fast as Hermes.

Swimming: Mera Swims like a fish and has taken to this swim style like a human walking on land.

Hydrokinesis: As the daughter of Poseidon Mera has absolute control and divine authority over water in all forms and states of matter, and has the same hydrokinetic powers as her brother Percy, only to an infinitely superior level. I will let the Authors know why at the end.

Powerful Scream: Mera has a voice of a Siren and can turn it into a weapon to enchant people or shatter eardrums. Her screams are something that is dangerous to even the gods.

Hydrogenesis: Mera can create water from his own power, generating it out of nothing

Water Immunity: Mera can fall from great heights into water, and is unaffected by any amount of water pressure. She does not get wet if submerged in water, unless she wants to. Mera can dry items underwater (as long as he holds onto it).

Water Propulsion: Mera can control the water around her to propel herself through water at incredible speeds. Where with her already fast speed in water makes her faster than Hermes.

Watercraft Manipulation: Mera possesses an intimate awareness of any ship she is on (sailing ships, canoes, motorboats, and submarines); being able to telekinetically operate one (as well as anything related to the ocean).

Perfect Bearings: Mera has perfect bearings on the ocean, so she can easily navigate her way at sea.

Water Solidification: Mera can harden water into an almost solid shape, and can use this power to walk on water.

Underwater Breathing: Mera can naturally breathe underwater.

Heat Resistance: Mera has a resistance to heat and burns, inferior only to that of Hephaestus.

Enhancing Healing: Poseidon has enhanced Mera ability to heal herself and people.

Cryokinesis: Like with Percy, Mera can control/manipulate sea ice since she has a greater level of control over water than her brother Percy does.

Aquatic Lordship: Mera has control and divine authority over all sea creatures, as well as many fearsome monsters native to the sea. In addition, can talk (normally and telepathically) to equines and sea creatures who mainly treat her with deference and lordly respect.

Geokinesis: Being Poseidon's daughter Mera can generate earthquakes.

Atmokinesis: Due to his control of the weather over the seas, Poseidon is also known as the God of Storms, being able to create fierce hurricanes as well as clear skies for sailors as he wished to. Hence, he is frequently referred to as "The Stormbringer". Mera has inherited this power from her father.

Electrokinesis: Mera can use lightning.

Aerokinesis: Mera can summon strong winds, which he could use to create storms such as hurricanes and typhoons.

Toxikinesis: Mera can control and manipulate poisons.

Mist Control: Mera can control the Mist; all Wizards in the Wizardry world have this ability gifted from gods who govern over magic. With mera being the daughter of Lily who was a witch & Poseidon who controls water. Mera's control over the Mist is comparable to Hecate's children.

Zoolingualism: Mera can understand and talk to marine animals, horses and similar creatures.

Expert Hand-to-Hand Combatant: Merais compared always to heroes of old; she is a grand master combatant when she has a Trident. Mera becomes an all-different force.

Mera's witch side: Mera's magical blood and power gives a boost to all her Demi God powers even boosts powers that a rare in Poseidon children. While unlocking new abilities.

It will be a requirement for Mera to do battle with Hercules when she is 16. The fight must end in a draw. When Mera is 17 she must be a warrior of the same league as Wonder Woman and just as deadly with magic. The author can choose if she can ascend to God hood, if so it would be required for Mera to ascend of her own power.

Mera gets into Hogwarts a month into the beginning of the first year. Poseidon sends one of his God children with her. The author can choose which God child it is. The challenge has to be in the Harry Potter & Percy Jackson books, no movies verse allowed.

Mera's Fatal Flaws

Personal loyalty & Excessive wrath: Because of Mera' experience with her Aunt Petunia and her Uncle Vernon. Mera has a deep wrath that brings about nature destruction. Storms, earthquakes', ice, toxic environment. When Mera has different levels of anger, deferent nature events happen.

Mera is loyal to people she holds in her heart, she would even choose her loved ones over saving the world. It will be a requirement for the Excessive wrath Flaw to be controlled when Mera turns 15.

Mera's Relationships

I will not go into many characters only some and will mention the main pairing, and one romance that Mera will have the author can decide on others but remember that Mera's final love will be the main. I will not go into much detail with the relationships. The author can do that.

Poseidon: Mera isPoseidon's first Demi God daughter and as so, he is very protective of her. While also being hard on her so that Mera can survive, he throws a lot of quest for her. Poseidon does pamper Mera a lot. Poseidon also wants to help Mera master her feelings because Mera reminds him of his old days and Poseidon does not want that for Mera.

Mera loves her father very much and knows she can get him to do things for her or change his mind about stuff. She is annoyed that Poseidon is hard on her and very protective which she calls him out on a lot.

In Mera's teenage years, Poseidon becomes overbearing towards Mera with dating boys and what she wears. Mera is Poseidon's favorite daughter and child while Percy is Poseidon's favorite son. Poseidon finds it amusing that Mera shares his humor.

Percy: Mera saw her brother in a dream when Percy was a baby, she find out that was her brother from her father Poseidon. While she was not angry with her father, Mera was worried for Poseidon having another child.

Mera calls Percy by his full name Perseus not Percy much to her brothers dismay. When Percy first arrives at the camp he was drawn towards Mera and had a crush developing towards her unknown to him that Mera is his sister.

Mera teasing of Percy makes the crush stronger, (Mera already knows whom Percy is). When Percy is later claimed by Poseidon, Percy was horrified about the feelings he had for Mera but got over feeling horrified about. Mera and Percy are closer than what a brother and sister should be but they don't cross the line more like having a foot on the incest line.

Luke: Luke and Mera are close friends, sometimes people mistake them for a couple mush to Thalia's dismay. Luke & Mera did date for a brief time but the interference of Poseidon and with Aphrodite, manipulating things from behind put an end to it.

Thalia: Thalia and Mera have a love/hate relationship mostly because of Luke and the power that Mera has. Thalia mockingly always call Mera the little mermaid or ginger princess to all other names. They fight like sisters all the time and consider each other rivals. Even though Mera saved her on their way to camp half blood Thalia is thankful but also she hates that her rival is so powerful.

This drives her to tamp into more of her Demi God powers that she does not use or like. However, as long as she can fight Mera on equal footing Thalia will even master her fears. Mera considers Thalia to be an annoying sister who is to bossy. Nevertheless, even though Mera and Thalia fight a lot they consider the other as sisters.

Zeus: Zeus is thankful towards Mera for saving Thalia, although he is very wary of her power. He does not know what to think of her so he has her do quest to judge her character. During the quests and many dream visits Zeus comes to like Mera.

In addition, in Mera's teenage years that like turns into love. This will be the main pairing for the challenge. Mera was also wary towards Zeus but began to tease him with her Poseidon brand sense of humor. Over the years, she begins to fall for him much to Poseidon's dismay.

Aphrodite: Mera and Aphrodite do not like each other, Mera is said to be more beautiful than Aphrodite, which the Goddess herself does not like. Aphrodite has a hand in Mera's failed relationships.

Kymopoleia: Mera and Kymopolia have a bad relationship, Kym is angry that Poseidon keeps her powers restricted but not Mera's powers given the power and potential Mera has shown. Therefore, Kym takes her negative feelings out on Mera.

James Potter: Mera and James do not get along, mostly because of James taking his anger toward Lily on Mera. James does not go too far with his treatment towards Mera for fear of Poseidon and Mera.

Dumbledore: Mera does not like Dumbledore for many things that goes on in the school that he had knowledge of but did not step forward. Dumbledore wants to see if Mera is the one who will defeat Voldemort but Dumbledore is wary of Mera's temper and power.

Mera gets in a lot of trouble during her years in Hogwarts, which often has one of her immortal siblings, her step mother Amphitrite or in rare occasions Poseidon himself come to the school , and often put own punishment by those carry Poseidon's orders.