From the introduction:
Are you interested in DMing but are afraid of doing your first attempt in front of a group? Maybe you have a friend that you think might be interested in D&D and are looking for a way to introduce them to the game. A two player module may be just what you need, all you need is a friend to play. One of you plays the role of the DM while the other is a player.
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You're on the road, traveling to your next destination. It's mid-to-late afternoon, and the day is warm with a slight breeze. The road curves around a large volcano, it hasn't erupted in several generations, but there's enough obsidian landslides that the road gives it a wide bank. The volcanic ash has made the land especially fertile and there's a large jungle that wraps around this half of the volcano.