Man, that's exactly what I was looking for. And do you know how did I find your addon? I searched for "Swarm" because I wanted L4D2 to be more similar to Alien Swarm in terms of infected's damage and HP. The other thing I want is NOT to have the map stupidly populated with infected but have some scenario of where and when do zombies spawn and attack players. But I guess that to accomplish this I will need to make my own map.