Z-Day - or Zombie Apocalypse Day - is approximately 36 hours on the day of October 31 in which zombies arise in our region. Some citizens in each country become mindless zombies, and begin to spread, converting other healthy citizens into more zombies. This is countered by nations researching the cure, and then spreading it to other nations in the region to convert zombies back into healthy normal citizens. Depending on the level of participation, Middle Earth could wind up as 100% zombies, or 0% if they are all cured. The more percentage of a region's total population is zombies, the more get created - so even a little bit of effort to cure some can potentially have a large impact later on. Once Z-Day begins, to cure zombies, set your nation to begin researching the Cure. After a couple of hours (I think it might have been 2 in the past?), you develop "cure missiles" to launch at other nations in your region. They hit and cure a percentage of the zombies in that nation - converting some zombies back into healthy citizens. You can not target your own nation with these cure missiles, however, so other people have to cure your zombies! Yay teamwork! Approximately every 20sec you can launch another cure missile - go to your target's nation page, and click the "launch" button. Note, however, that for approximately 2min after you get hit by a missile you can not fire any yourself. Yay coordinated teamwork!
Every 10-20 minutes Nationstates increases your nation's zombie count based on how many zombies you currently have. Also, every hour all nations in a region get a number of new zombies based on the zombie population of the rest of their region. So, even if your nation manages to get down to no zombies, if other people in you region still have some, you will get more. This amount greatly varies with the average percent zombie population of your neighbors. Victory only happens if all nations in a region have zero zombies (however, note that if an infected nation immigrates to a clean region, the whole process can start over). So, basically, zombies spread like a highly contagious disease.
What you can do now:
Make a note on your calendar for Oct 31-Nov 1. The assault typically lasts between a day and 36 hours - on Halloween day. Resolve to spend as much of that time as you can helping to defend Middle Earth. Even if the time you spend is short, every little bit helps our region. Last year Middle Earth did very well, ranking highly among the regions of the world in terms of the number of survivors. A high ranking brings our region prestige and visibility, helping it grow and remain vibrant over the upcoming year.
What you can do at the very start of Z-Day:
Log in, and set your nation to begin researching a cure. This will take some time - probably an hour or two. As time goes on, your "cure missiles" will become more potent. So, best to start early!
What you can do the rest of Z-Day:
At any time you have a spare moment, log into your nation and launch some cure missiles at your neighbors in Middle Earth. A cure missile converts a small percentage of zombies back into normal living people, so its most effective to target those nations with the greatest absolute total number of zombies. Any nation that launches at least one cure missile and does not intentionally attack others with undead hordes will get a special, limited edition "Badge of the Barrow-Wight Slayer of 2020". To see who has the most zombies in our region, go here:
What you should not do on Z-Day:
Intentionally attacking other Middle Earth nations with undead hordes ruins other peoples' hard work. So, we ask if you want to embrace and aid the Barrow-Wights, please be considerate of your neighbors and do it from a different region, and then return to Middle Earth after Z-Day is complete.
Lastly, regardless of what happens to your nation over Z-Day, everything is set back to as it was before the event started. So, nothing is risked by participation.