Cyclone

Head back to Castle Fynn. The Cyclone is tearing through the landscape north of Fynn, and you'll need a Wyvern to get inside. Before entering, grab the Blood Sword from Paul's stash in Fynn; it makes the Emperor fight almost trivial. All 7 chests inside the Cyclone are permanently missable.

Mysidian Tower to Castle Fynn

Board your ship from Mysidian Tower and sail south to exit the circular mountain range surrounding Mysidia. Head slightly east, then north to return to the mainland. Bolt Fish still appear in the sea; Sergeants and Sorcerers patrol the land. Cross the continent on foot (canoe over small bodies of water) to reach Castle Fynn. You can't miss the Cyclone; it's visible from the overworld.

Castle Fynn

Once you arrive, climb the staircases until you reach the throne room. Talk to Hilda and she'll mention the Cyclone keyword. Learn it and ask about it. She confirms the only way inside is by air, and fortunately there's still one Wyvern egg left.

Return to the ground floor and take the stairs in the bottom-left corner. Climb the next staircase as well, then walk up the narrow corridor and through the door at the end. Use the Pendant on the mirror to trigger a cutscene. The last Wyvern egg hatches and the Wyvern flies straight into the Cyclone, giving you a ride inside.

Before heading into the Cyclone, stop by Paul's house in Fynn to collect 8 chests. The world map changes after this chapter, so grab everything now.

Fynn: Paul's Stash

Exit the castle and enter the town of Fynn. Paul's house is in the bottom-left corner of the map.

Talk to Paul and ask about the Cyclone. He admits he's been hoarding equipment and offers to share it with you.

Walk to the bottom-right corner near his bed where a hidden passage leads through the wall. Inside you'll find 8 chests containing armor upgrades (Black Garb, Ruby Cuirass, Gold Cuirass, Silver Cuirass, Gold Hairpin, Thief's Gloves), an Elixir, and the Blood Sword. Equip it on your strongest physical attacker immediately.

Equip what you can and restock at the Fynn shops before heading out. The Cyclone is a one-time dungeon.

The Cyclone

Walk the short distance from Fynn to the Cyclone and interact with it. The Wyvern drops you inside.

The dungeon is a vertical climb through winding corridors connected by staircase after staircase. Electricity panels cover portions of the floor and deal 1 HP per step to each party member. Not dangerous on its own, but it adds up across seven floors.

Eyemoeba (1,140 HP, 100 ATK) is the only missable enemy here and it hits hard. Lamias (1,000 HP) can charm party members, which is worse than it sounds when your Blood Sword wielder starts attacking allies. Vampire Ladies (1,140 HP, 85 ATK) drain HP with their attacks, so fights against them tend to drag. Cockatrices still show up with their petrification Beak; Gold Needles should be stocked by now. And if you run into a Hill Gigas or Werepanther on the upper floors, don't be surprised by the damage spike.

1F-3F. From the entrance, follow the winding corridor to the first staircase on the right side and climb up. Head left for Chest 1 (Ripper) in the top-left corner. Backtrack down and take the long path left to another staircase at the end. Descend and veer left for Chest 2 (Poison Axe) near some electricity panels, then return to the 1F starting area.

1F-4F. From that first staircase, head left and take the middle passage to reach 2F. Continue left, then down, and climb the first staircase on your left to 3F. Turn left again and ascend the next stairs to 4F. The path splits here: left fork leads to Chest 3 (Diamond Gloves) while the right fork holds Chest 4 (Diamond Helm). Grab both and head back down to 3F.

3F-5F. Continue along the main corridor to the next staircase leading to 4F. Turn right and climb the left stairs to 5F. Veer left and follow the corridor down (avoid the electricity panel path branching right) to find Chest 5 (Defender). Proceed down and left for Chest 6 (Diamond Armor), guarded by 2 Generals (1,800 HP, 120 ATK, 120 DEF each). These are the toughest random encounter-level enemies in the dungeon; Berserk and the Blood Sword cut through their defense. Return to 4F afterward.

4F-7F. Take the right staircase to 5F and continue up to 6F. Circle north around the corridor to Chest 7 (Wind Flute), guarded by a Green Dragon (3,000 HP, 150 ATK, 150 DEF). This is the hardest chest fight in the dungeon, so heal up before opening it. The Green Dragon resists Poison; use lightning-based spells instead. That's all 7 Cyclone chests. Climb the nearby stairs to 7F for the confrontation with the Emperor.

Boss: The Emperor

The Emperor fight is three consecutive encounters with no breaks between them. The Blood Sword makes this entire sequence easy because it deals percentage-based damage that ignores defense, and the Emperor's 3,000 HP turns into fuel for the wielder. Heal your party to full and equip it before climbing the final stairs. The Royal Guard waves are handled with basic physical attacks; save your MP for the Emperor's Barrier and Slow spells.

The Emperor sends 3 more Royal Guards immediately after the first wave. Use the same approach, then he steps in himself.

Return to Castle Fynn

After the fight, you're transported back to Castle Fynn automatically. The Dark Knight Leon has declared himself the new Emperor, and a series of cutscenes plays out. Talk to Hilda and she'll mention the Palamecia keyword. Learn it and ask her about it.

Speak with Leila and Gordon as well. Ask them both about Palamecia and they'll mention that Paul has bragged about breaking into Castle Palamecia in the past. Time to pay him another visit. But before you leave, note that most towns on the overworld are destroyed and inaccessible from this point forward. The overworld enemies have also been replaced with stronger creatures, so save before heading out.