With the phoenix statues on either side of the Big Drawbridge now lit, it's possible to call down the bridge. Watch Yoichi fire an arrow, then use Inferno to light it on fire. Watch the cutscene that ensues.
Once at Ryoshima Coast, follow the narrow path to a pair of signs that point in opposite directions. Follow the path to the right and heading north. Further ahead, a wall needs to be blasted open with Cherry Bomb, granting access into a cave with a large water bed. Head upward through the cave and other dried-up water beds will be seen. Transfer the water from the lower beds to the higher ones with Waterspout, eventually filing the moat around the wilted Guardian Sapling. With the sapling rejuvenated, Bloom must be used to bring it back to life and clear Ryoshima Coast of the cursed zone.Visit the dojo on a small island. There, the Holy Eagle technique which grants Amaterasu a double jump ability can be learnt. With the ability learned, return to land and head to the end of the peninsula directly north-east of the now-sunken Goryeo. The top of the Moon Turret there can be reached to get a view of the waters surrounding the ship and the crescent symbol surrounding it. Use Crescent to bring out the moon and clear the waters surrounding the ship. The ship may be entered, but there's nothing can be done in there just yet. For now, check out the north-western edge of Ryoshima Coast to find the entrance to Sei'an City.