But the hero seemed as villainous as the foreman, and the mysterious masked riders, for once, appeared really sinister.

As singularly silent as when he had entered the cab, the mysterious rider had effected a disappearance.

The mysterious rider swung the sack once around his head and loosed it.

My respect for our mysterious rider grows each day.

The are also intrigued by a "mysterious rider" who seems to be sending messages to someone in the ranch house.

Yet scarcely a mile farther the mysterious rider turned north across the vast expanse of the dry lakes, pointing toward distant Yellow Peak.

She would discover that she had not really been saved from freezing to death by a mysterious rider and been warmed by his body.

Dendybar had used his magic to track the mysterious rider all the way from the mountains and had pointed the soldier in the right direction.

Or was it the mysterious rider who had come dashing out of the broken country to the dead town?

It first appeared in episode 12 with its mysterious rider (a robot programed to destroy Phantom Knight).