As soon as we can’t hear the hum — that low, undulating sawtooth tone that all their craft make — we run for the entrance. We know they’ll see us. They always see us. Smash and grab, in and out as fast as we can manage, get back underground and figure out what we scored.
This time they sent something down after us, something new: looked like metal spider with another metal spider welded to its back upside-down. Rusty speared it with a sharpened pole. There was something alive inside, part of it, grafted onto the circuitry.
Rusty cooked and ate it.