I believe zombie re-spawn mechanics will be a key towards keeping us threatened throughout the game. How so? Think minecraft; in minecraft; monsters have a chance to spawn wherever the light level is under a certain threshold. What do you do first in minecraft to survive ? Block monster spawn at your safe-place by lighting it up with a few torches. We recently got a re-spawn parameter in the sandbox options; basically my point is it's own limitations are by far too strict. How so? Spawning is limited in tiles you have visited within your sandbox interval AND tiles inside you have created player contraptions. - First, building a single barricade will limit re-spawn in an entire tile - Secondly, a tile if i recall correctly, is a HUGE square on the map (think an entire block of houses) I think the re-spawn mechanics are currently mis-tweaked as it inevitably will only work on tiles you have not played yet, therefor not changing anything in your own game-play. Once you've cleared the street you live in, you're probably not going to see anything happen anymore. Then there's also the problem of making zombies you haven't loaded actually roam as hordes.