[Astromancer]

This is a simple idea, have the manna distortion that has made the Great Desert an arid No Manna area suddenly shirnk. Move the border of the Great Desert and the No Manna area attached to it move seventy-five miles west.

I'm assuming that the No Manna Area is cause by a distortion in the Manna field of Yrth. And that this Manna Distortion causes the Great Desert. So move the Low/No manna border seventy-five miles west, and the desert will do the same.

What all this does is open up thousands of square miles of empty farmable land for poor peasants to move onto and farm. A bonanza to those nobles who organise it well. This also brings many treasures and mysteries long ignored into either easy or practical access.