This was one persistent illusion! They knew it for what it was, yet it remained as clearly as before.

"But it's dark in here," Chex's voice came.

"Darknevv divturbv you?" Volney asked. "I have no problem with it."

"Suppose there's a wall or something?" she demanded. "I'm not worried about a mountain of illusion falling on me, but I don't want to bang my face."

"I can lead you," Volney said. "Volev never go b.u.mp in the night."

They set up a column, with Volney leading and Esk at the rear. They marched along the approximate route of the path, but it didn't matter since there was no mountain. At times Esk saw the light that shone down the tunnel and highlighted the contour of the rock, with Chex's body pa.s.sing in and out of it; the effect remained eerie. But as they penetrated more deeply, the light diminished, until all was dark.

"Vtop!" Volney exclaimed abruptly. "There iv a chavm!"

"A chasm!" Chex echoed. "Can we go around?"

"I will ekvplore." They waited while the vole moved along, first to one side, then the other. "No, it crowev the full region."

"You're sure it's not an illusion?" Esk asked, half facetiously.

"Quite vure. I cannot tell how deep or wide it iv, but it iv definitely prevent."

"Perhaps I can fathom it," Chex said. "I can explore it with my staff." There was the sound of the staff tapping. "It is too deep; I can't find the bottom." Then, "But I can find the far side! It is not too far; I could hurdle it."

"I cannot jump," Volney said. "But I could tunnel under it, if there iv rock below."

"Maybe that's best," Chex agreed.

There was the sound of rapid digging. Then there was the noise of splashing. "Oopv! I cannot tunnel through water!"

"Well, we got you across the lake," she said. "We should be able to get you across the chasm. After all, it's not exactly of the scope of the Gap Chasm."

"Can't tell," Esk said. "The Gap Chasm has extensions that jag a long way north and south. This could be one of those."

"You are not much help," she said.

"Maybe we could help him cross," Esk said. "We have our staffs; if we made a temporary bridge-"

"No, they aren't long enough. I touched the far side only at full extension."

"Well, if we tied them together-"

"They would bend in the middle, and then the ends would slide off."

"But if we stood on either side and held on to them-"

She considered. "Perhaps. But we would have to be very sure of our hold."

"You truvted me to lead you," Volney said. "I will truvt you to hold me."

They used the length of vine Chex had thoughtfully saved to bind the ends of the two staffs together as securely as was feasible. Then she made a leap in the dark and landed on the far side of the chasm. Then Esk poked the lengthened pole across, and she caught hold of it.

Now Volney donned his gripping talons-it seemed he had several sets for different applications-and took hold of the staff. He was not, as he had said before, a climber, but he could cling to a small root, and this was similar in diameter. He moved carefully out over the chasm, while Esk clung tightly to the end.

The pole sagged, for the vole's weight was formidable. Then an end slid toward the brink as the staffs formed a V in the center. Esk now regretted his notion; he was afraid that something would break, and Volney would be dumped into the dark depth. Fortunately he felt his ogre strength coming into play; he would not let Volney fall.

Then the pull changed. Esk's staff angled further toward the horizontal. The vole's weight was now on Chex's staff.

"I tire!" Volney's voice came. "I cannot climb!"

"Esk, let go your end!" Chex called.

"But-"

"I'm going to haul him up! Let go!"

Hoping he was doing the right thing, Esk let go. His staff immediately slid over the brink and clattered down.

But now there was the sound of motion. Chex was using her centaur strength to pull her pole up, the vole along with it. There was a rasping and a clatter. How was it going?

Then Volney's voice came. "I am here!" It was from Esk's level; the vole had reached the far side!

"I'm glad," Chex gasped. By the sound of it, she had been tiring too; her human arms were weak compared to her equine legs.

The rest was routine. Chex made sure Volney was all right, then leaped back across the chasm. Esk got on her back and she made one more leap, carrying him across.

Then they proceeded on through the mountain, and finally emerged into daylight on the south side. Esk knew that his relief was no greater than that of his companions.

Before them stood the castle. It had a moat and a solid outer wall. The drawbridge was down, and on it was a big empty cage.

They stopped just before the moat. "The Good Magician's castle is always beset by challenges," Chex said. "That is because the Magician doesn't want to be bothered by querents who aren't serious. But I don't see what kind of a challenge an empty cage would be."

"I've heard that the challenges are always slanted toward the visitors," Esk said. "Does an empty cage mean something to one of us?"

They exchanged glances. None of them had a notion.

"I suppose we could just go on in," Chex said. "But I distrust this. It is never supposed to be easy to get in, and if it seems so, then that must be a false impression. I would much rather understand the situation before committing myself."

Esk could only agree. "But how are we to understand it, if we don't go farther?"

"Oh, we should be able to reason it out to some degree," she said. "The intellect is always superior to blind action."

"That's not the ogre view," Esk said.

"We have uved vome intellect and vome acvion," Volney said. "If one doev not work now, we can try the other. But I find it odd that we have encountered vo many challengev on the way to the cavtle, and none now that we're here."

"That is strange," Esk agreed. "It's almost as if the challenges were in the wrong place."

"Or were they?" Chex asked, her wings flapping in her excitement. "Could that be the way the Good Magician planned it?"

"But aren't they supposed to be at the castle?"

"We a.s.sumed so, but how do we know? The Good Magician makes his own rules! He could have put the challenges anywhere along the route."

"But if they are slanted for particular visitors, how would the right ones be there for the right visitors? There are three of us."

But her excellent centaur mind was operating now. "I think he knew we were coming, and from which directions we were coming, so he could have set things up for each of us that the others wouldn't encounter."

"But he didn't!" Esk pointed out. "We all encountered the little dragons."

She looked at the cage. "Look-there are dragon droppings in there, and the bars are soiled with soot. Those little smokers were in there, but they got out!"

"They were let out," Volney said. "That cage hav a clavp only a human paw could operate. Mine couldn't."

"Why would they be let out before they were used?" Esk asked.

Chex shook her head. "I don't have the answer to that, but let's see if we can work it out. We three arrived together, and we helped each other get here. Does that seem usual?"

"No," Esk said. "I thought it was supposed to be one at a time."

"Well, let's pattern it. If things hadn't gone wrong, who would have come here first?"

"You would. You overshot the intersection; otherwise you would have arrived first, and then me, and finally Volney."

"So it seems reasonable that the Good Magician was setting up for me first. Now what would have been good challenges for me?"

'The mountain!" Esk exclaimed. "You're claustrophobic, so you were afraid to go into the tunnel until you realized that it was all illusion."

"And that could have been my first challenge," she said. "To figure out the nature of the mountain, as I certainly should have done, because of my dam's map. But I failed that challenge and turned back."

"Then I failed it too, because I was with you."

"But if you had come alone, you would have gone on through the tunnel, because you aren't claustrophobic," she said. "So it wasn't a challenge for you; it didn't matter whether you caught onto its nature."

"But that chasm inside-that would have stopped me, if I didn't fall into it."

"Whereas I had no trouble with that," she said excitedly. "So maybe those were two challenges, one for each of us, set up together because we were likely to arrive so close together that there wasn't time to set up complete alternates. It is making sense!"

"The lake!" Volney said. "I could not crow the water! That wav my challenge! And the chavm too, becauve there was more water below it, ekvending down and down."

"Yes. Because we were with you, we got you across, just as you got us through the mountain. We helped each other past each other's challenges! I doubt we were supposed to."

"But what about the little smokers?" Esk asked. "We did not release them."

She contemplated the open cage. "I think that collection of dragons would have been a formidable challenge for any of us. How could we have gotten by that?"

"I might have," Esk said. "I could have climbed over the cage, and said no to any that tried to grab me through the bars."

"True. So that wasn't your challenge after all. But it would have been much more difficult for me or for Volney, because we don't climb. Just hanging onto our staffs across the chasm was all he could do. I suppose I might have tied a line to the cage and hauled it out of the way, but he-"

"I fear I would have had to turn back," the vole said. "Unlevv I had thought of your idea to uve a raft, then uved the branchev to fill hi the chavm vo I could crovv that too."

"But as it happened, someone released those dragons, and we encountered several along the paths," she said. "We really must fathom that mystery before we can make sense of the larger picture."

"Obviously, something is wrong," Esk said. "Those smokers weren't meant to be loose, they were meant to be caged, and only get loose if the challengee messed up. Someone cut off the challenge before it started."

"So it seems," she agreed. "Would the Good Magician himself have done it?"

"I don't see why. If he didn't want the dragons here, he would not have brought them."

"The Gorgon, then?"

"She wouldn't mess up what he set up!"

"I agree," she said. "Could someone else have done it?"

"It doesn't seem likely."

"So we are left with the inexplicable," she concluded. "Perhaps now it is time to enter the castle, expecting the unexpected."

Esk nodded consent, nervously. Volney did not look any more comfortable.

They stepped on the drawbridge. They hauled the empty cage off, then crossed on over.

Suddenly an ogre loomed up before them. The thing was monstrous and hairy and ugly, and both Chex and Volney retreated in alarm.

But Esk's reaction was opposite! "Grandpa!" he exclaimed.

But it was not Crunch Ogre. It was some other male, not quite as ugly, but still quite formidable. It blocked their way.

"We're only coming to talk to the Good Magician," Esk said, strongly suspecting that this would not provoke any reasonable response. "Will you let us by?"

He was correct. The ogre ope'd his ponderous and marbled maw and made a bellow of rage that shook the castle.

How was he to get past with his companions? Esk realized that this was a challenge, and it was his to meet and solve. But almost nothing could make an ogre stand aside; he was in a position to know that. Nothing except- Except another ogre. There was the key!

But Esk could not invoke his ogre self just because he wanted to. It came of its own accord, when triggered by erratic circ.u.mstances.

Still, sometimes it was possible to arrange the trigger. It was risky- but so was standing before an ogre as if ready to be eaten.

"Wish me luck," Esk muttered back to the others. Then he strode forward, directly into the ogre.

For a moment the ogre was startled by this temerity. Then it grabbed for him with a ham hand.

Esk saw that meat hook coming, and his ogre nature reacted. Suddenly he roared, his ogre strength surging. "Go 'way, me say!" he bellowed, and bit at the other's paw.

The other reacted astonishingly. It shrank away, literally; as it retreated, it became smaller, until it looked very much like a man, and Esk towered over it. But Esk, his ogre dander up, wasn't satisfied; he smashed at it with his own ham fist.

Something shattered. Fragments of gla.s.s flew out, and the other ogre was gone. Esk stood before a man-sized frame from which jags of gla.s.s projected.