In The Lanes Between
Sora, Riku and Kairi were riding their gliders to the next world on their journey.
"So, what do we do now?" Sora asked.
"What else we keep trying to stop them." Riku said.
"Hey, guys I think I can see that we are heading to another world." Kairi said.
Sora and Riku looked ahead and saw the world Kairi mentioned. It was Atlantica they could see a city under water and above the water were a bit of land.
"It's Atlantica!" Sora said.
"There's hardly any land we'll drowning." Kairi asked.
"Don't worry Kairi we just need a little bit of magic." Sora said.
Atlantica: Undersea Courtyard
The moment they entered the world they entered the water and their armour disappeared.
Once it was removed Sora saw he was in his merman form, except he had his crown necklace around his neck. When he looked at Riku and Kairi he saw that they had changed forms as well. Riku had a dolphin tail and a dorsal fin like Sora except Riku's tail was sliver and his dorsal fin were slightly longer. Kairi has a rose red tail with paler red, translucent fins and was wears a pink clam-shell bikini top and her pearl necklace around her neck.
As soon as Kairi saw herself she blushed. Both Kairi and Riku found it hard to swim.
"This is embarrassing." Kairi said trying to swim.
"It's not that bad." Riku said.
"Easy for you to say." Kairi muttered.
Then Sora headed something and turned around to find swimming their way was Sebastian and Flounder.
"Sora, welcome back." Flounder said swimming around him.
"Nice to see you again mon but who are they?" Sebastian asked pointing his claws at Riku and Kairi.
"Their my friends Riku and Kairi." Sora said as they tired to swim. He looked back at Sebastian. "If you don't mind can you show them how to swim?"
"No problem mon." Sebastian said. It took a few minutes, but Riku and Kairi where now swimming much easier. "Das it, you got it now. By da way Sora where are Donald and Goofy?"
"They're on a mission of their own. Speaking of missing friends where's Ariel?" Sora asked.
"Oh, I forgot you won't here. King Triton made her human and now she's married to Prince Eric." Sebastian said.
"That's great." Sora said.
"And you're just in time they'll be coming here soon with their new daughter Melody." Flounder said.
"Well, let's go and meet them." Sora said.
"Of course, but first let go to King Triton." Sebastian said.
With all five of them swam towards the palace.
Atlantica: Triton's Throne
A few moments later they entered King Triton's Throne room and found him wishing around his throne.
"Your Majesty we have visitors." Sebastian said. King Triton turned around and saw Sora, Riku and Kairi.
"Ah, the young Keyblade bearer welcome back and I see you have brought some new faces. I am King Triton the ruler of this world or at least the ruler of its seas." King Triton said.
"I'm Riku." Riku said bowed.
"And I'm Kairi." Kairi said bowing as well.
"You're just in time to see Arial and my newly born granddaughter." King Triton said. Then a seahorse swam towards King Triton and floated next to his ear.
"Your Majesty the ship is here." The seahorse said.
"Then tell everyone to swim to the surface." King Triton said. Then the seahorse swam away. King Triton then turned to face everyone else. "We better swim to the surface."
With that he grabbed his Trident from its resting place and all six of them swam towards the surface.
Atlantica: Ship
They came up to the water surface they saw a ship it was as big as the Black Pearl and had a mermaid figure head. Also the ship was covered in flowers and there were tons of people. They could hear drums and trumpets then all around them Mermaids, Mermen and different sea creatures swam to the surface.
Then they saw walking to the side of the ship was Ariel who was wearing a white dress with a white bow in her hair and Prince Eric and in Arial's arms was a baby girl with black hair wearing a pink and white dress and her bow in her hair what also has the same colours. Then Ariel saw Sora down on the water and smiled at him.
"Sora, your back, but where are Donald and Goofy?" Ariel asked.
"I'm afraid they had another mission and couldn't make it, but I did bring my friends Riku and Kairi." Sora said.
"Well, it's nice to meet you both and you couldn't have come at a better time, say hello to my baby girl, Melody." Ariel said showing her.
King Triton smiled and created a column water so he could reach the deck. He then pulled out a golden locket that was shaped like a shell with Melody's name on it.
"My precious Melody, I'm giving you this locket, so you'll never forget that a part of your heart will always belong to the sea." King Triton said.
He then opened the locked and a glowing orb came out and took the form of the city of Atlantica. Then beautiful music began to plan while Mermaids and Mermen swam around it. As the music played Melody smiled and laughed as the music played making both Ariel and King Triton smile.
But then out of nowhere a tentacle shot out of the water and grabbed Melody. Then out of the water came a woman with white hair and green skin she was half human and half octopus. She looked a bit like Ursula but she was younger and thinner and had green tentacles one of which was holding Melody. She was riding two manta rays that swam around the water scaring most of the Mermaids, Mermen and sea creatures.
"Who is she?" Kairi asked.
"Morgana Ursula's crazy sister." Sebastian said who was hiding next to the ship with Flounder.
"I didn't miss the cake and ice-cream did I?" Morgana asked.
"Morgana!" King Triton said. Then he got angry while his trident glowed. "Surrender the baby or I will-" Morgana then used Melody as a shield stop King Triton from blasting her.
"Ursula would have simply loved to come but something came up. Now, uh, what was it?" Morgana said as she climbed onto the ship. "Oh yes. You all SHISH-KABOBBED HER! One minute you're on top, the next you're sushi! And I see that the Keyblade brat is here, how perfect and I've got a friend who is dying to see you."
"Who are you talking about?" Sora asked.
"She's talking about me." A voice said.
Everyone turned around to where the voice was coming and saw coming out of the water was Vanitas. Like them he had changed form into a merman only unlike them he had a shark's tail and a dorsal fin which were both black as night.
"Vanitas!" Sora said.
"Sora, he looks like and sounds like you." Ariel said shocked.
"Except we are nothing alike, because unlike him I can do this." Vanitas said clicking his fingers.
Then out of the water came giant shark. It was blood red with an icy blue underbelly and in the middle of it had they could see the Unversed logo. It swam around close to Morgana and opened its mouth directly below Melody.
"What do you two want?" King Triton asked.
"Well, I want the trident as for him." Morgana said pointing at Vanitas. "He already got what he wants, but he would like the Princess of Heart."
"Princess of Heart but there isn't-" King Triton said then it hit and turned to face Kairi. "Well, you're not getting her or my trident."
"I would reconsider or your precious granddaughter will be food for the Unversed." Morgana said dangling Melody over the Unversed shark.
"Fine, you win you can have my trident just don't harm little Melody." King Triton said.
"And you can have me." Kairi said.
"Kairi, are you sure?" Sora asked.
"Sora, we don't have a chose." Kairi said.
"Well, well, I get the trident, Vanitas gets the princess, avenge poor unfortunate Ursula and gain all the power of the ocean and it's not even ten o'clock, Hmm, hmm. Not a bad morning." Morgana said.
Ariel then grabbed Eric's sword and cut a rope which was connected to a yard.
"Hit the deck." Eric said ducking.
The yard then hit Morgana in the chest freeing Melody. Eric grabbed a rope and swung towards Melody to catch her, but Vanitas then jumped out of the water having the same idea. But Sora jumped out of the water and tackled Vanitas and they both dived down into the water. Eric then grabbed Melody and swung back to the boat.
"Should we help Sora?" Kairi asked.
"No. Right now we got to take this Unversed out." Riku said.
They then summoned their Keyblades and pointed them at the Unversed. They then dived under water and before the Unversed could do anything they jumped out and slashed at it leaving a giant x on its forehead. King Triton then pointed his trident at the Unversed and fired a beam of magic at in the middle of the x making it disappear.
"This isn't the end Triton it's just the beginning." Morgana said created a ink cloud in the water.
"After her." King Triton ordered.
Then his guards swam towards her but before they could reach her she and the manta rays disappeared.
"You'll never find me, but I'll find you and your precious granddaughter." Morgana voice yelled.
"We shall not rest until that mad women is vanquished. Find her find her." King Triton said firing a magic blast into the clouds.
"I hope Sora is having better luck." Kairi said.
Atlantica: Undersea Courtyard
While everyone was deal with Morgana on the surface both Sora and Vanitas were battling under water.
Vanitas fired a Dark Firaga spell at Sora that sent him into an underwater cliff. Sora looked up in time to see Vanitas coming towards ready to stab him with his Keyblade. Sora swam up and Vanitas plunged his Keyblade into the cliff trapping it. Sora then swam down and slammed his Keyblade on to Vanitas sending him crashing down to the sea floor.
"You've certainly gotten better, but is it you or Ventus that is fighting me?" Vanitas asked.
"You can stop with the mind games, it's not going to work." Sora said swimming towards Vanitas.
"It must be working, because you just fell into my trap." Vanitas said.
Then suddenly several tentacles grabbed Sora. Sora looked at what had grabbed him it was a bunch of octopus Unversed with the logo on their heads. They had grabbed Sora with their tentacles making it impossible for him to move.
"Pathetic and he I thought you could be challenge. I would like to stay here and chat but I've got a princess to kidnap." Vanitas said and then started to swim to the surface.
Sora tried to get himself free but it was no use. All he could think about was protecting Kairi and wishing he had the strength to do it.
Suddenly Sora began to glow making Vanitas to turn around. Then he was blinding in a bright light and it faded the Unversed that had Sora trapped had disappeared. Then Vanitas noticed that Sora was welding another Keyblade in his other hand and not just any other Keyblade but Ventus's Keyblade.
"To answer your first question both me and Ventus are fighting you. Together!" Sora said.
"It makes no differences I'll take you both out right now." Vanitas said summoning his Keyblade.
Vanitas then swam towards Sora and slammed his Keyblade towards him. But Sora blocked it with Ventus's Keyblade and hit Vanitas in the chest with his own Keyblade. Vanitas was thrown back and crashed into some corale he placed his arm around his stomach in pain and looked at Sora.
"Have you had enough or do you want some more?" Sora asked.
"Oh, you have no idea. But obviously I can't get the princess today, but I will and I'm not going back empty handed." Vanitas said pulling out a familiar looking seashell.
"Wait, isn't that Ursula magic seashell?" Sora asked.
"Yes, it is." Vanitas said.
"But, last time I was here I destroyed it." Sora said.
"True but a Vessels of Darkness can't be destroyed it took a whole year for it to regenerate. I'd like to stay and fight, but I've got to go" Vanitas said then he opened a Corridor of Darkness and swam towards it.
"You're not going anywhere." Sora said swimming towards Vanitas.
But Vanitas entered the Corridor of Darkness which disappeared the second he entered.
Atlantica: The Shore
Everyone met at the shore near Eric's palace everyone was wearing a sad face.
"I'm sorry. There's no sign of Morgana she's vanished." King Triton said.
"The only good news, is that Vanitas won't be showing up again." Sora said.
"By the way Sora, why did he look so much like you?" Ariel asked.
"He's the living embodiment of the darkness in by heart and he's a member of an organization trying to let darkness run free." Sora explained.
"We are sorry to say we can't help you to find Morgana." Kairi said.
"We understand, but until Morgana is found Melody can't go into the sea and nether will I." Ariel said.
"But Ariel-" Flounder said.
"I'm sorry Flounder, but if Morgana is anything like Ursula she'll never give up." Ariel said and removed the locket from Melody and handing it back to King Triton. "This is the only way, Melody can't know about other Worlds, the Keyblade, merpeople or Atlantica or even you daddy."
"Very well, Ariel, your right." King Triton said swimming away. He then turned Sebastian before leaving. "Sebastian you will what over her."
"Me!" Sebastian squeaked he then fainted.
King Triton then looked back and continued to swim towards the ocean Flounder then followed him. Sora, Riku and Kairi saw Ariel and Eric taking Meldoy back to the palace they. Then saw King Triton dropping the locket into the ocean before he and Flounder dived underwater.
"I wish we could help them." Kairi said in a sad tone.
"So do I, but we got to stop the Organization before they do anymore harm." Riku said.
With that they started to glow and fly up into the air and through a portal.