Shifting sands periodically uncovered the artifacts of long-vanished makers. But all was silence. Mars was a tomb. He persisted, invading every crevice, every nook, exploring every molecule (for Ixmal knew the mind-force potential. Indeed, Zale-3 might be as minute as the single-cell protozoa of his own brackish seas. Never mind, he would find him.) In the end he surrendered, baffled. Zale-3 was not on Mars. * * * * * Delusion? Had seven hundred million years of nothingness produced an incipient psychotic state? He worriedly confided the fear to Psychband, reluctantly submitting to hypnotic search. Finally he emerged to reality, cleared by Psychband. "Some feelings of persecution but not approaching delusory state," Psychband diagnosed. "Zale-3 exists." So, the other had lied! Ixmal contemplated a machine capable of deceit and immediately analyzed the danger. Zale-3 had lied, therefore it had motive--and dishonest motive implied threat. Threat without aggression was meaningless, hence the other had the means. He must work fast! Ixmal gridded the solar system: every planet, every moon; each shattered remnant that drifted through space, the asteroids and orbital comets, even the sun. Seventy-two hundred years later he detected his enemy--a small plasto-metallic cube crouched atop a jagged peak on Callisto, Jupiter's fifth moon. Ha, far from being the master of Mars, his opponent was locked to a small satellite--a mote in space. And he had presumed equality! He searched closer, attempting to unlock Zale-3's origin. (What had happened to its makers?) Ixmal felt a guilty pang. He scanned Zale-3's world contemptuously. Then he saw it--movement! Zale-3 squatted immobile; but on the slope of the hill a strange building was taking shape. It was little more than a cube, but its design? Its purpose? He knew somehow that the strange building was related to his encounter in space with Zale-3's mind, thus it was connected with him. Ixmal hurriedly flashed a panic call to Psychband. "Psychokinesis--Zale-3 has learned to move matter by mind," Psychband pronounced. "But how?" Psychband gave an electro-magnetic rumble, the equivalent of a shrug. "Out of my field," he said. "No prior indoctrination." Ixmal sensed a momentary fright. The alien could move matter just as Man had moved matter. The factor of controlled mobility ... directed mobility. Clearly Zale-3 was no ordinary god. He'd have to speed his efforts. Time was running out. Already the earth pattern had changed since his first contact with the alien. Ixmal concentrated. The earth rotated, revolved, changed. In a long-forgotten memory cell he found a clue--Man once had frustrated the laws of probability in the throws of dice. He devoured the hidden knowledge. Although little enough to go on, he detected a basic principle. * * * * *