The Mightiest Man

This e-text was produced from “Worlds of If” November 1961. Extensive research did not uncover any evidence that the U.S. copyright on this publication was renewed.
He had betrayed mankind, but he was not afraid of the consequences—ever!
They caught up with him in Belgrade.
The aliens had gone by then, only a few shining metal huts in the Siberian tundra giving mute evidence that they had been anything other than a nightmare.
It had seemed exactly like that. A nightmare in which all of Earth stood helpless, unable to resist or flee, while the obscene shapes slithered and flopped over all her green fields and fair cities. And the awakening had not brought the reassurance that it had all been a bad dream. That if it had happened in reality, the people of Earth would have been capable of dealing with the terrible menace. It had been real. And they had been no more capable of resisting the giant intelligences than a child of killing the ogre in his favorite fairy story.
It was an ironic parallel, because that was what finally saved Earth for its own people. A fairy story.
The old fable of the lion and the mouse. When the lion had exhausted his atomic armor and proud science against the invincible and immortal invaders of Earth—for they could not be killed by any means—the mouse attacked and vanquished them.
The mouse, the lowest form of life: the fungoids, the air of Earth swarming with millions of their spores, attacked the monstrous bodies, grew and entwined within the gray convolutions that were their brain centers. And as the tiny thread-roots probed and tightened, the aliens screamed soundlessly. The intelligences toppled and fell, and at last that few among them who retained sanity gathered their lunatic brethren and fled as they had come.
If he had known the effect the fungoids would have on them, he would have told them that too. He had told them everything else, when he had been snatched from a busy city street, a random specimen of humanity to be probed and investigated.