Stage 9 takes place in a rice field. Four long sections are connected by three of the six underground passageways. You can use them to take advantage of the time savings they provide, but it isn't entirely necessary. You have more than enough time to explore the entire region and exit through the gates at the end. A slightly different cast of enemies make their presence known here, but none of them are necessarily more dangerous than any enemy you've previously encountered.
Dungeon entrance: 600. Another difficult dungeon to navigate without a map. Clear out the upper portion of this dungeon before collecting all of the items from the lower portion and exiting.