All I want is an easy to run dungeon crawl with some interesting magical features out of the box for a pick up game. I won't have the time to do major prep for the game such as internalizing a whole village's worth of relationships and secrets. I was considering the lead one from the Kalamar collection Harvest of Darkness but it seemed very rough for a solo player, and I considered Return to the Keep on the Borderlands but the sexual aspects and alignment changing magic and babylonian cult were not the themes I was looking for. I can use out of the book MM stats for most of the monsters in Cloudland without a problem and I've already got some ideas for the elf interactions. Besides, I'm a sucker for law chaos conflicts like the one page intro Cloudland has as a background.
And I wanted to use something from my shelf that I have not used yet.