He returned to his immediate situation. "If the goblins have Proton weapons, we'll need Proton defenses. They are probably making ready to storm this hill. We should have light, bulletproof armor, laser screens-"

"Personal force fields," Sheen suggested. "They will handle a combination of attacks, and I can conjure in such small units without alerting the enemy Adepts."

"And make invisibility-spells for the rest of us," Brown added. "They'll know we're near the Phazite ball, but still-"

"Yes," Stile agreed. "Probably they won't want to fire their shots too close to the Phazite; they won't have effect, and if they did, what would it be? There's power to destroy the planet in this dense little sphere; no one would gain if that energy were suddenly released."

"Most likely they will attempt to wipe us out, and send the ball rolling back down the spiral tube," Sheen said. "Then they will blast the entrance closed and wait for the juxtaposition to terminate. Clef surely can't hold it much longer."

"We're committed to our present course," Stile said, shaking his head ruefully. "They gave us full opportunity to go beyond the point of retreat. I'd like to meet the goblin commander; he's one smart tactician."

"Maybe an Adept is running things," Brown said.

"This smacks more of field tactics to me." Stile brought out his map. "As I make it, the ball has a fairly straight path north from here. All we need to do is clear out a few obstacles in the channel and start it rolling. We don't want to mire it in the lake, unless that's beyond the juxtaposition zone. Trool, where is the north side of the curtain now?"

"It is stabilized north of the lake and north of the Oracle's palace, in this section," the troll replied. "There is some curve in it yet; elsewhere it impinges the White Mountain range, but here it is fairly southerly."

"And where is it in this section?" Stile asked, indicating the place where the Oracle-computer was buried, somewhat removed from the Oracle's palace.

"It slants northwest, passing just south of that region. But that is not a good place to roll the ball anyway; there is a long incline up, with the curtain almost at the ridge there. Much easier to roll it through the valley to the east."

So the curtain was just south of the Oracle-computer. That was why there had been no news of the computer's crossing; Clef's Flute had not been able to broaden the juxtaposition zone enough. That meant the curtain would have to be stretched northward a little — and how would Stile find the creature-power to accomplish that, in the midst of battle?

"Nevertheless, I believe we'll roll it across at this site," Stile said, after reflecting a moment. "I hope the giants arrive in time to help; they'll be able to roll it barehanded."

"I'm not sure," Sheen said. "The ball of Phazite is the same diameter as a giant's finger — but its substance is fifty times as dense as living flesh. Trying to push on it could be clumsy and painful."

"They can use silver thimbles, or roll it with a pool cue," Stile said, smiling briefly.

"And the route," she said. "Why roll the ball across that particular place?"

Stile did not want to express his notion openly, for fear the enemy was somehow eavesdropping. "Because it will be difficult, slow, but certain; the enemy will not have barriers entrenched there, and no special traps, and our time will be running out."

"That's not fully logical," she protested. "The enemy will not guard that region well, because the natural terrain represents a formidable defense. They will have time to regroup while we struggle to push the ball up the hill."

"Maybe," Stile agreed.

"I hope your illogic has some redeeming aspect."

"I think thou art crazy," Brown said succinctly.

"We'll clear a course that curves northwest," Stile said. "They may assume it's another ruse. Then we'll roll the ball along it as fast and far as we can and hope for the best."

Trool faded out for another survey and returned to report that the contingent from Proton was arriving. "Flesh and metal men," he said wonderingly.

"Cyborgs, maybe. Robots with human brains. They can be very effective. It's time for us to move." He looked around the chamber. "I want the golem crew to remain here, to start the ball rolling at my signal. Timing is essential. Brown will supervise them. Sheen and I will sneak out and clear the path. Trool will act as liaison."

"I want to sneak out too!" Brown cried.

"What about me?" Clip asked, in man-form.

Stile had been afraid of this. He had to devise legitimate jobs for everyone. "Thou canst go report to thy herd," he said to the unicorn. "In thy hawk-form and with a spell of invisibility, thou canst get through to tell the Stallion of our situation." Stile turned to Brown. "But thou — if thou shouldst go, who will guard the book?"

Her brown eyes widened. "The book of magic?"

"If the enemy gets its hands on that, we're finished. We dare not take it out to battle. Sheen has memorized the spells she needs; she doesn't need the book with her now. So it is safest with thee and thy golems."

Brown's eyes fixed on the book, round with awe. "I guess…" she breathed.

The main reason Stile wanted her here was to keep the child out of the worst danger. Any protective spell they might make might be negated by a specific enemy counter-spell. The book did need guarding, so it was a valid pretext.

He left with Sheen, using an invisibility-spell as well as the protective shields she had fashioned before. He doubted the two of them would remain undiscovered, but with luck, the goblin army should be distracted by the detachments of serfs, robots, and animalheads.

They started down the slope, using conjured spades to eliminate troublesome ridges. This, too, was risky, since the changes they made were visible, possibly calling attention to their otherwise invisible progress. Most of the slope was all right, with a natural channel requiring only touching up.

But as they got away from the ball, the illusion fashioned by the enemy Adepts faded. They saw the goblins ranged about the base of the hill, pistols drawn. The moment there was any visible action at the top of the slope, the goblins would start firing.

Even in this hiatus, it was bad enough. Detachments of goblins were building a series of obstructions near the base of the slope, wedgelike barriers with the sharp ends pointed uphill. If the Phazite ball encountered a wall crosswise, it would crash right through; but these wedges were oriented to deflect it efficiently off-course, where it could be further deflected by the natural channels below, until it was stuck in some cul-de-sac, and the game would be lost. That smart enemy commander's handiwork again! "Our work is cut out for us," Stile said. "One misplay, and we lose the ball. Conjure me some plastic explosive and detonators that can be set off by magic invocation. I'll have to mine some of those barriers."

"That sort of thing is not in the book," Sheen protested. "No plastic explosive with magic detonators! But I can get you one-hour timed explosive."

"That will do. Just let me know when the hour is up so I can get clear."

She conjured the explosive. It was high-grade; a kilogram had enough explosive power to blast away all the emplacements they would have time to mine. They walked on down the hill.

The contingent from Proton was marching toward the hill. Stile realized that it was on the wrong side of the illusion-spell and did not perceive the goblin army; the goblins would ambush it, wiping it out before it had a chance to organize. "I can't let that happen," he muttered. "I haven't been much of an organizer; my allies will be cut down, trying to help me. I must warn them!"

"If you show yourself, you will be cut down!" Sheen said. "My spells won't save you from attack by the entire goblin army, backed by the magic of all the Adepts."