The Last Story/Mysterious Forest

Exorcising the Skeleton army
Speak to Mirania, who is standing in the room just before the stern, looking through some boxes of herbs. After talking about her past, she asks to be allowed to go ashore. Tell her "Then let's go ashore". You're taken to a deserted island. Open the gate in front of you, then follow Mirania into the maze-like structure. After the cutscene, head forward slightly. Skeletons have suddenly filled the area. Lure them out one-by-one with the crossbow, then take them when they're alone. Ignore the one in front of you for now; instead, head to the right. At the corner, there should be a Skeleton down the path. Hide behind the wall to the left, shoot him, get him alone, and Slash away. Next, head down to just past the pillars, and hide behind the left one, back to the wall. Take out the Skeleton down the path here. Now return to the party, and head past here towards the gate. Turn right, cross the raised structure with four pillars, and hide behind the left corner of the end of the wall to your right, where you can see another Skeleton in Seek Mode. Lure him down and Slash him. Head down to where he was, and hide behind the pillar to the right, back to the wall. Shoot the nearby Skeleton, and defeat him. Only one left. Head forward slightly, to where the previous Skeleton was, and hide on the right side of the alley to your right. Take out the Skeleton down the alley with the usual method. A flawless victory. Be careful not to alert more than one Skeleton at a time - if you take one out in front of another, the survivor will call in an army of powerful subordinates. After all are defeated, rejoin your party at the gate at the back of the area (not the gate by the four pillars that you passed earlier).

Chase Mirania
When you enter Seek Mode, look down at the giant footprint on the ground. Then, enter Seek Mode manually, and look at the gate. It's covered in ivy, so Yurick burns it off with a fireball. Mirania then rushes off. Chase after her. In the next area, follow the path provided by the water. On the island it leads to, you're faced with Mystic Plants and Reptids (including one on an inlet to the right). Focus on the Reptids first, or Yurick will struggle to find time to cast his magic (use bombs to get ones you can't reach). If you get caught by a Mystic Plant, shake it off with. When all are dealt with, keep following the path through the water (at the fork, left leads to a Summon Circle, right leads on to Mirania). Head through the thin path. More Reptids and Mystic Plants. Take them out, then follow the sound of Mirania's screams.

Boss: Mystic Spider
This beast is like most spiders you've faced before - guarded front, weakened rear. This one has one crucial difference, though - it can eat your allies, putting them out of commission for the entire battle. If it shoots silk at you, shake quickly to break free, then use Gale to free whoever it's trying to consume (in order: Mirania, Yurick, Dagran, you; it'll keep trying Mirania until it gets her, and so on). Watch out also for the smaller Sylvan Spiders, who can paralyse you with their attacks; if you've learned Gathering Burst (during Gathering, guard and block attacks successfully at least three times, then press to unleash the built-up energy), it can kill several at once at maximum charge. As with any other spider, though, you have to get around to its back, and strike, or else use Gathering to keep it facing you, and have Dagran attack its behind. Keep attacking until the Spider dies. After the battle, follow the party through the forest. Head up through the thin path. At the end is a skeleton, apparently that of the forest's Guardian.

Back on the ship, if you haven't yet been to the Shipwreck, find Yurick in the staircase room just before the captain's quarters, and speak to him to go there. If you have, upon returning to the main deck you'll be greeted by a crewman, who tells you that the door he was repairing (just before where Yurick is) is fixed. Head there to advance the storyline.