From Introduction:
In the remotest part of the desert, there stands an ancient tower. Abandoned long ago by some forgotten civilization, it is nonetheless a place that sees the most remarkable of visitors. Slug people from beyond the stars come here to ride their flying carpets. They are rare, however. Some who have made the forbidding trek out to this remote building say they have waited days or even weeks to see this singular sight. But they also say it was worth it.
This tower once held a magic gateway, used to bring strange beasts to this world, perhaps so they could fight in the arena. Or maybe they were used to guard the riches of the wizards who build this portal, who can say what the ancients did, now that their works are so far in the past? These visitors use the gate because they enjoy the acoustics of this site. The warm sun, the soft sand, and the strange tower — this, apparently, is what makes it a tourist destination.
These intelligent slugs have only recently been introduced to
the human concepts of light and vision. While they are interested in such abilities, too many of their wizards who have come here to experiment with such foreign notions have been driven mad. They used spells to evolve their bodies, but then they did not stop. Their bodies warped beyond recognition and their motivations became as alien as this world is to them (and theirs is to us). Thus it is rare for them to venture further out than this tower, which they enjoy too much to shun completely. The acoustics, you see, are just too good.