Walkthrough:Kingdom Hearts/Atlantica

Atlantica

Just before you enter this world, a breef scene will show Sora being concerned about entering this world, since they will drown if they enter it. Donald then tells him that his magic can allow them to suvive.

Upon landing, you'll see that Sora now has a blue dolphin tail, Donald now has octopus legs and Goofy has become a sea turtle. You'll then be introduce to Ariel, Flounder and Sebastian, who will teach you how to swim. You mostly have to follow Flounder around. Soon, a bunch of Heartless will appear, and your new friends will hide in a clam. After defeating the Heartless, attack the clam to let your friends out, revealing a save point (type 2). Ariel will then join the party.

Your main object now is to reach the palace. You must follow the tritons on the walls to reach it. You'll also notice that the Heartless are very different than the ones encountered in other worlds, though the Search Ghosts can also be found in Halloween Town. Once you reach the palace, three Screw Divers will follow the party, but King Triton (who are know introduced to) will vaporise them. He'll dismiss the claims of a Keyhole, and will forbid Ariel from leaving the palace. She swims off. You can find her at her Groto.

In the Groto, the music will change, and you'll notice a strange shape on the wall. Now you must follow the dolphin that swims around the area back to the Undersea Valley. Once you reach that area, grab onto it (make sure there are no Heartless around) and it will take you to the Sunken Ship. Inside of the ship, you'll find a tresure chest containing a talisman that might just fit into the wall. However, just before you open it, a shark will smash the ship, creating a hole big enough for the party to go through. He'll begin to attack the party at random times, so be very careful and insure Sora's health is topped at all times. Now you must return to the groto. The easiest way is to use a shortcut found near the ship, and use the rapid water sprot to push a treasure chest out of the way.

During the cutscene, King Triton will show up and destroy the talisman, casuing Ariel to swim off crying. He'll also exile the party out of his world. However, the save point where you met Ariel will not allow you to leave. Meanwhile, Ursula will trick Ariel into helping her take the triton from King Triton. Once you reach the palace, you'll notice that Triton is wounded, and that Ursual has made off with his triton. Ariel is determaned to get it back, and will then rejoin the party.

Head back to the Sunken Ship, and you must now fight the shark. Once he is defeated, Sebastian will open a hidden tunnel. There is a save point at one part of the tunnel, so you'll be able to save and heal. At the end of the tunnel, you'll encounter Ursula.

After defeating her, she'll disapear into what appears to be a portal. You'll then learn Mermaid Kick, which is needed to reach Ursula for the second battle with her

After defeating Ursula, you'll be taken back to the palace, where King Triton will tell you that the world's Keyhole is in Ariel's Groto. Head to the Groto (don't worry about the Heartless now, since they won't attack the party now), and then Ariel will use the triton to reveal the Keyhole, ending Atlantica's story.

If you want to get 100%, you will need to return to Atlantica to perform the Trinity Detect, which can be found in the courtyard by the palace.