le for a prisoner to win. Practically speaking, this
has happened on an average of 3.5 times out of a hundred."

Barrent looked up at the gallery of spectators. To judge by their dress,
they were all men and women of status; high in the ranks of the
Privileged Classes.

Then he saw, sitting in a front row seat, the girl who had lent him her
gun on his first day in Tetrahyde. She was as beautiful as he had
remembered her; but no hint of emotion touched her pale, oval face. She
stared at him with the frank and detached interest of someone watching
an unusual bug under a jar.

"Let the contest begin!" the loudspeaker announced.

Barrent had no more time to think about the girl, for the machine was
rolling toward him.

He circled warily away from it. Max extruded a single slender tentacle
with a white light winking in the end of it The machine rolled toward
Barrent, backing him toward a wall.

Abruptly it stopped. Barrent heard the clank of gears. The tentacle was
withdrawn, and in its place appeared a jointed metal arm which ended in
a knife-edge. Moving more quickly now, the machine cornered him against
the wall. The arm flickered out, but Barrent managed to dodge it. He
heard the knife-edge scrape against stone. When the arm withdrew,
Barrent had a chance to move again into the center of the room.

He knew that his only chance to disable the machine was during the pause
when its selector changed it from one killing mode to another. But how
do you disable a smooth-surfaced turtle-backed machine?

Max came at him again, and now its metal hide glistened with a dull
green substance which Barrent immediately recognized as Contact Poison.
He broke into a spring, circling the room, trying to avoid the fatal
touch.

The machine stopped. Neutralizer washed over its surface, clearing away
the poison. Then the machine was coming toward him again, this time with
no weapons visible, apparently intending to ram.

Barrent was badly winded. He dodged, and the machine dodged with him. He
was standing against the wall, helpless, as the machine picked up speed.

It stopped, inches from him. Its selector clicked. Max was extruding
some sort of a club.

This, Barrent thought, was an exercise in applied sadism. If it went on
much longer, the machine would run him off his feet and kill him at its
leisure. Whatever he was going to do, he had better do it at once, while
he still had the strength.

Even as he thought that, the mac