The Gun by Philip K. Dick

Nasha clicked on her hand lamp, shining the beam down the stairs. The steps were thick with dust and rubble. At the bottom was a steel door.

The Eyes Have It by Philip K. Dick

There was no doubt of the thing in the next passage. Julia, whom I had thought to be the one normal person, reveals herself as also being an alien life form, similar to the rest.

The Defenders by Philip K. Dick

They stepped out of the car. A leady was approaching them rapidly. It coasted up in front of them and stopped, scanning them with its hand-weapon raised.