Zombie Evolution - How Does It Work?

In 0.C-3782? Weird. Don’t remember seeing that particular widget, must have missed it.

Anyway my main concerns with this were: A) are we looking at an “end state” in zombie evolution where everything is a Hulk or a Brute thereby making being on foot in a populated area for anything but the shortest sprints completely unplayable, and B) how many in-game seasons do these “dark days” (more accurately: days of you are completely fucked) take to arrive on the default settings?

Also do regular Zeds (or for that matter, Zeds with professions, Zombie Cop, Zombie Firefighter, etc.) “evolve” into Grapplers, Grabbers, Spitters, Shockers, Smokers, Acidics, Corrosives) too? Where does the Evolution start? Is every Zombie destined to one day be a Zombie Hulk or do only Tough Zombies have the potential to HULK OUT? I’m filled with questions about this. I should probably get on GitHub and start figuring out some spoilars.