Under the Sea
Atlantica presents its own unique set of challenges, particularly with controlling your characters. Underwater combat and maneuvering can be a difficult thing to get a hang of. Fortunately, upon entering Atlantica, you are given a brief tutorial on how to handle the new changes to your characters. Shortly after this introduction, the Heartless show up and ruin the fun, so get rid of them and then attack the large white shell where Sebastian and Flounder are hiding in order to let them out and reveal a Save Point.
Ariel suggests heading back to the palace, which you can find by simply following the large gold trident markers engraved on the walls throughout all of Atlantica. Follow the first one to reach the Undersea Valley. This is a massive, wide-open room with lots of nooks and crannies to explore. Though there’s a lot of places to explore, for the sake of getting to the palace, follow the trident markers to an opening in the wall that leads to the Calm Depths.
The Calm Depths are actually not all that calm. There are high-speed currents preventing you from exploring the two areas to your left (at least until later), so follow the current to the right and hug the right-side wall, which will dump you in a circular cavern with an upward-facing current in the center. If you get caught in the current, it will blast you back up into the Undersea Valley, so avoid it and pass through to the other side to enter the Undersea Cave.
The Search for Sunken Treasure
Head straight up in the Undersea Cave to access the Undersea Gorge, another rather large area that is full of areas to explore. For now, follow the trident marker to Triton’s Palace and swim straight through to Triton’s Throne for a cutscene. Afterwards, return to the Undersea Gorge locate the dolphin swimming around. Examine it to grab a hold of its fin and ride it around a few times. It doesn’t go anywhere now, but this step is imperative for progressing through Atlantica later. Release your hold on the dolphin, then make your way to the large boulder in front of a cave and push it aside to access Ariel’s Grotto. Inside, you’ll find a rather depressed Ariel.
After the cutscene, be sure to scour the grotto for the various Treasure Chests. Leave the grotto and return to the Undersea Valley, where you’ll find the dolphin that was previously in the Undersea Gorge. If you didn’t ride it around in the gorge, it would still be there, and you wouldn’t be able to move forward. Clear the Undersea Valley of Heartless in order to examine the dolphin to grab hold. The dolphin will drag you against the strong current in the Calm Depths and give you access to the Sunken Ship area.
Head down into the ship through the opening in the top. Approach the Treasure Chest to trigger an event in which a giant Shark attempts to attack. After it fails to get through the window, it’ll swim away, leaving the Treasure Chest behind. Open it to receive the Crystal Trident.
Boss: Shark
HP: 200 / EXP: 100
When you try to leave, the Shark will be waiting for you outside the ship. Despite its nasty biting attacks, the Shark isn’t much of a threat. A few combos will make quick work of this battle. The Shark will reappear randomly in the Sunken Ship area every time you return to it, so be on the lookout. Defeating him isn’t that hard, and you get 100 EXP and a chance for a Mega-Potion every time you defeat it!
Looking for the Keyhole
Return to Ariel’s Grotto for a cutscene in which Triton destroys the Crystal Trident in a fit of rage. After the lengthy cutscene, return to Trident’s Throne to find Ursula stealing the trident after her search for the Keyhole. With Ariel now in your Party, return to the Sunken Ship area. Take out the Shark again if it appears, then locate the large rock toward the back of the room near a half-buried ship. Sebastian can reach the button on the rock wall behind it to open up an entrance to the Den of Tides area.
Follow the path to the right until you reach a small room with a single white shell in it. Attack it to open it up and reveal a Save Point. Use it if you wish, then head back to the fork in the Den of Tides and head down the other path until you reach Ursula’s lair.
Boss: Ursula, Flotsam, & Jetsam
Ursula – HP: 450 / EXP: 1000
Flotsam – HP: 60 / EXP: 150
Jetsam – HP: 60 / EXP: 150
Your rumble against Ursula and her lackeys can be a little chaotic. Ursula will mainly attack by spinning around the room, knocking out some decent HP whenever she makes contact. Flotsam & Jetsam will swim around and attack with tail whips and lunging attacks. These two nuisances can be easily defeated for a quick MP Recovery (and trust us: you’re going to be using a lot of MP in this battle). Whenever you defeat Flotsam & Jetsam, it only knocks them out temporarily. They’ll rejoin the battle after a few minutes of being knocked out.
Your target, despite what you might think, is not Ursula, but her cauldron in the center of the room. By launching magic into it, the cauldron will overload and explode, knocking Ursula out for a little while. That’s when you can attack her directly with everything you’ve got. Eventually she’ll wake up again, most likely reviving Flotsam & Jetsam when she does. Repeat this pattern until her HP is reduced to zero.
Victory Reward: Mermaid Kick Shared Ability
Locking Atlantica
Ursula has fled to a section of Atlantica that you have thus far been unable to access. But with the newly acquired Mermaid Kick, you can now swim upstream in the Calm Depths and reach the cavern opposite of the entrance to the Sunken Ship area. This new room, labeled ???, is where you can find the sea witch and take her down for good.
Boss: Giant Ursula
HP: 900 / EXP: 1500
Giant Ursula’s a much more formidable foe this time around, and with the trident in her possession, her magic is even more deadly! The Aero spell is key in this fight, as it provides a much-needed buffer against Giant Ursula’s assault.
Your target is her face, which can be difficult to reach at times when she is constantly raining lightning bolts down around her. Aero can reduce the damage dealt by these attacks for the most part, but every now and then, you should break away to use a Cure and then swim back in.
The rest of Giant Ursula’s attacks can be pretty easy to avoid, especially with the new Mermaid Kick. Whenever she tries to suck you into her mouth, swim in the other direction using the Mermaid Kick to avoid being chomped on. Giant Ursula will give you ample warning for the rest of her attacks, such as the bubbles that will follow you and deal damage when they pop. Mermaid Kick away and they’ll disappear on their own. The massive lightning blast that she fires from her mouth is also announced well in advance, and can be avoided by swimming away. Finally, if she ever raises the trident, swim away from her quickly to avoid being hit by a very nasty lightning storm.
Continue hammering her face with combos, and make sure to keep Aero equipped for the majority of the battle. Before you know it, the once mighty Giant Ursula will fall.
Victory Reward: Ansem’s Report 3
Defeating Ursula returns you to Triton’s Throne. With his trident returned, King Triton gifts you with the Thundara magic spell. He also asks that you seal the Keyhole, which you can find in Ariel’s Grotto. Return there to lock Atlantica for good and receive the Crabclaw Keyblade. Locate the nearest Save Point and return to the World Map and select the last available world in the second ring of worlds.