Zombie Despair
It is an advanced theory which says one zombie dies from despair for every 2 killed in the same zone each night.
Formula: Zombies died from despair = (Number of zombies killed - 1) / 2
The image shown is a table instructing players how many zombies they should kill to completely clean the zone of zombies (by tomorrow). The zombie icon displays how many zombies are in the zone, the 
Machete representing how many zombies the player should kill with weapons (or other methods), and the 
death icon representing how many zombies will die at 23:59 due to despair. In theory, if a player were to follow this table and kill the exact amount of zombies as instructed, by the next day the zone will be completely cleared of zombies.
The idea behind this is that it will save the need to use resources to kill some zombies, as melee weapons require 
to repair, and ranged weapons require water or a 
Battery to use.
Note that, while the zombies will always die of despair, the zone might not appear completely cleared the next day. This is because zombies will still respawn in the empty zone if any of its adjacent zones is infected.
