The Deathdream
When you get to the Forest of Myth, save your progress at the entrance’s mailbox. This next part will be long, and some might consider it boring; so make sure to save it now. Once you speak to the mayor, the next section will be composed of about 20 minutes of reading a story. You’ll be unable to quit out of this until you’ve reached the conclusion.
During your reading, you’ll be asked to answer some riddles. The riddles and their correct answers are listed below. Once you’ve gotten through the whole story, you’ll complete the mission and obtain the Sealed Verse, Dark Execution. Return to Popola to begin the next mission.
- One with it is lacking. Two with it is ideal. Three with it is dangerous. What is it?
- "The answer is… a secret."
- I enter through the window, but break no glass. When night falls, I vanish. What am I?
- "Sunlight!"
- I have four legs in the morning and two at noon, but end the night with three. What am I?
Helping the Other Villagers
After you rescue the mayor from his dream, you are able to speak to the other two people in the town. They’re also trapped in the Deathdream. Each of them takes about 5 minutes of reading. They’re optional, though completing them both earns you the one-handed sword, "Faith." This weapon is necessary for unlocking all the endings in the game; however, even if you do not help the other villagers, you can still buy the sword at The Aerie during Part 2 of the game.
Full video walkthrough for the Forest of Myth available via this link, starting at 27:11The villagers' dreams play out as “choose your own adventure” stories. The woman's dream involves navigating a maze and the man's dream contains a logic puzzle. The details of the dreams seem to be randomized each time you attempt them. 
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