Free Cube Route by Piers Anthony

agreed, smiling. “Meanwhile I regret to say that I seem to have lost the mirror you gave me after all.”
        “I'm sorry. It seems I can't give it away.”
        “What is the mission?”
        “That's awkward. You see, I can't tell you about it unless you join it, because it's supposed to be secret.”
        “I certainly won't join something blindly,” Karia said. “Centaurs are known for logic, not gambling.”
        “Yes, and I need a logical mind, because I'm not sure mine is up to it. I also need nine Companions, and all I have so far is one.”
        “Nine! Have you any idea how to get them?”
        “Very little. Except that he told me they would be suitably rewarded.”
        “Rewarded? In what manner?”
        “He didn't say.”
        The centaur shook her head. “We appear to be at an impasse. You can't tell me about it unless I commit, and I can't commit until I know about it, if then.”
        Cube hadn't anticipated this problem. That of course showed why she needed a good mind along. She wished for the moment that she had the ability of one of the louts in her home village, who could see from any part of his body. He had many points of view. That might enable her to get a different perspective. Then a bulb flashed brightly over her head.
        “I saw that,” Karia said. “You just had a bright idea.”
        “Yes. A logical idea. Let me try it on you.”
        The centaur shrugged, her front moving in a fashion Cube envied. Her own front would never bounce or ripple like that. “Let me have it.”
        “You were probably the person going to see the Good Magician before me. The questioner.”
        “The querent.”
        “Querent?”
        “A person who queries.”
        “Oh. Yes. You were the querent right before me, only you didn't get through, so then I was the next.”
        “True.”
        “So maybe there was just one mission, and whoever came with a Question would get it, in return for her Answer.”
        “That seems likely.”
        “The Good Magician told me that when I completed the mission, I would be beautiful. That I would get what I wanted.”
        “That is the normal course,” the centaur agreed, not quite evincing impatience at this rehearsal of the obvious.
        “But if you had made made it through, it would have been your mission.”
        “Agreed.” Karia was polite, but her tail was switching restlessly, causing little clouds of lightened dust to rise.
        “And maybe your problem would have been solved at the end of it.”
        “Perhaps.”
        “The Good Magician didn't tell me he would make me beautiful after I accomplished the mission. He told me I would be beautiful. My impression was that it would happen when I got there.”
        “The Good Magician's Services often do work out that way.” Now her mane was wavering, as her impatience worked its way forward.
        “So if you had done it, your problem would have been solved right there. Not because you had completed your Service, but because that is where the solution is.”
        Karia paused a third of a moment. “That is an arguable case.”
        “So if you go there now, you may after all have your Answer, despite not seeing the Good Magician. And that might be your reward for participating.”
        “That is by no means certain, but by no means uncertain. Perhaps there is an even chance.” Then the centaur made her decision. “I will join you. If you are correct, I will have my desire, and if you are incorrect I will still have what may be an excellent adventure.”
        “Wonderful! Now I can tell you all about it.” She proceeded to do that, and Karia listened and nodded.
        “Counter Xanth. Things are surely different there, and perhaps the laws of magic differ, so that our liabilities differ too. That might indeed cure me. In any event, it