I'm stuck on the soft shell creatures at the water pump. How do you kill them, and what do you use?

Aim for their soft underbelly. Attacks bounce off their shell, but going for the torso or head will work.

Well it all depends on your weapon but they do have heavly armored shells, so yeah aim belly, head or extremities:)

If you can, try to hit them in the face as that's their weakest spot. I've killed them a variety of weapons, though I think the combat rifle was actually the easiest kill. Grenades work well if you're fast enough... or land mines if you're not.

A flamer tends to make short work of them as well.