Randall Garrett: Anything You Can Do
The alien had looted and killed for 5 years on earth. The time had come to have him meet his match.

The Alien did not intend to crash land on earth, but he did. The alien tried to communicate with humans, but he could not. The alien did not wish to be captured, and so he wasn't. For over 5 years he roamed, looting and killing as necessary. Why could the combined forces and brains of all the nations on earth not deal with him or it? Well, Earth was faced with a strange problem indeed. They had to have a superman. And there weren't any available. So perhaps one had to be made....