So I started up a map and tried to spawn zombies in with the toolgun. However, when I did so, the zombies didn't show on my screen. They were 100% there because I could bump into them and hear them, but I can't see them. When I spawn a combine/rebel next to the zombies they get ready to fight, yet they don't fire. I tried uninstalling and reinstalling it, that didn't help. I know the problem isn't the map either because I spawned them in before and they still showed up. The other thing is that it only affects regular zombies. Fast ones, zombines, and poison zombies all work fine. Tf is going on?