User blog comment:CyborgKing/brown mob shot and gone/@comment-4501235-20120105074336

There have been times when I thought the Brown Mob disappeared after I shot it. Then I figured out that it doesn't handle corners very well. What I mean is; once it's been aggravated it will get stuck if it hits an inside corner.

Say I was looking down from my tower and "m" represents me, "L" represents a group of blocks higher than the surrounding surface (the blocks make an L shape on the moon's surface) and "*" represents the brown mob. If our positions were  * L m    the brown mob would keep circling my tower. If our positions were  m L *   it would get stuck in the corner. Since the top of the brown mob blends in so well it's hard to spot from above. One time I thought I had lost a brown mob, I came down from my tower and was walking away when it exploded. Turns out I just didn't see it.

I'm not sure if that's what happened to you. If my explanation wasn't clear, let me know and I'll try to get a photo to post. After your post, just to check, I did find a brown mob, built a tower and shot it until it died. It still took about 8 shots to kill, with a Slugpistol v1.