One of the monster types that can spawn in a game of Zone Alfa is swarms of creatures. I didn’t have any in my collection and thought that they might be tricky to scratch build so I bought a few from the Reaper Bones collection.
4 bases of rats, and 2 each of spiders and beetles should be enough for my purposes. They were fun and quick to do too. The Reaper Bones models are made of a funny plastic but they took (brush on) paint well. I’ll be getting some more of them.