First off I'm very surprised and impressed at how good the movie was. The degree of character development, which lead to me actually caring about these people, lead to me to researching what was wrong with Nux / writing here! Anyway.. I believe "Half-Life Warboy" pretty much says it all. They're tumors from the radiation (half-life) and they're killing them ALL.

I believe Half-Life Warboy pretty much says it all. They're tumors from the radiation (half-life) and they're killing them all.