In the country of Marrachia magic users are hunted down ruthlessly by the red guard. There is however one place that is safe and that is the mountain castle of Than'akh (which s not a name I just made up on the spot, <cough>). Situated high up on a mountain, the only way to get there safely is by magic. Once a year the teachers of the school take the trip into the lowlands to see if there are youth who knows magic. From there they give them an offer of joining them, away from the fears of being hunted down.