You can get 2 extra skill points if you click on the "share on Facebook" and "share on Twitter" buttons that appear when you click on the small tab on the top-center of the map screen.
They will be awarded even if you don't actually share the game.
So in short: expand, expand, expand: gather survivors as soon as you can (having a second Leader early helps), but remember to send a soldier or two to accompany Leaders wherever needed; I usually don't accept a risk of more than 10% (unless I have Leaders to spare).
Aim for the building types you need; prioritize living accomodations (if you don't have enough), fortifiable buildings (Malls, Police Stations), Church/Pubs or places that can become them, farms and places that can become farms; scout far and wide every time the number of recruitable spots is zero or close to zero.
Make sure that, along the way, you get at least 1 Lab, 1 School, 1 Hospital; although I managed to win acquiring those three later in the game and focusing *exclusively* in sustaining my growth rate.
-I cared about having room for new people more than producing food;
-I scavenged pretty much all my food from places, rather than growing it;
-I achieved self-sustainability of food well after the point where I became sure of winning; I have been at 0% happyness for quite some time, as a result of not being able to throw parties;
-I didn't had a school until mid-game, but trained all the "normal" Survivors into Soldiers by having them defending the fort;
-I didn't care about minimizing the perimeter of my base, but rather expanded quick enough so that, as part of my expansion, I was killing zombies around me at a steady pace;
-My fort has been breached just 3-4 times in the whole game, and I never had to have more than 30% chances of failure.
Just finished at Nightmare, 1 minute ago.
I must have got lucky, because it was easier than when I finished it at Harder.
My starting point featured a Police Station (not immediately accessible, on a diagonal angle), a Big Farm, an Apartment and a Trailer Park. And one important thing: there were 4-5 recruitable groups of survivors in the 10 blocks around me, which allowed me to develop my forces faster than the zombies.
I have been VERY bold on the first 3-4 turns - sending Leaders to scout far without escort, having civilians to kill zombies, sending lone soldiers to clear areas, scouting at large, ecc. - and although my own character died in the second turn, I eventually managed to expand very quickly (of course I would have considered resetting my game if things got out of hand).
WTF Why did I lost all my savegames?!?! This is worse than the game being bad, being it so nice and ruining the enjoyment after I invested 10+ hours into it. ONE / FIVE, that is 1/5.
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