Suddenly, there was a sharp whistling sound coming at us, and before I could turn to face it I felt something very nearly clip the tip of my ear.  I ducked instinctively and glanced up, just in time to see a missile whiz straight over my head.  It continued on its merry way, slamming into a rock further ahead of us and exploding on contact.  My head snapped around to catch sight of what was shooting at us.  It was a sentry bot, one of the ones I’d been working on before all this had happened.  It’s guns were spraying wildly in our direction, making me silently thankful I hadn’t managed to calibrate their targeting software yet.

The story is here if you are interested: https://www.fimfiction.net/story/397060/fallout-equestria-broken-oaths