Apparently I'm one of only 164 people to finish the hard badge. Basically, you need to keep restarting your game until you have a couple big farms near you, one hospital, and a bunch of bars/churches. Police stations and malls are a plus, but not necessary. Personally I went for the evil portal finish, simply because soldiers are always great on things other than the win condition. I researched up to the +2 to food production, and then converted everyone except for 2 leaders and a couple builders into soldiers. I used the two leaders to party, and just turtled for the win.
Suffers from the same "circle to win" mentality that all of the other games of this genre suffers from. Main cannons and shoulder weapons are all useless (except for maybe the last ones). The only weapons you need to upgrade and get are 4 SMGs (slot), and then jump up directly to 4 laser slots. Everything else is a waste of money, because this game is too easy to require anything else. The game gets "harder" by putting more things on screen at the same time, which doesn't really increase the difficulty because the enemies simply don't do enough damage. All more enemies really do, is decrease the FPS of this game and make it lag on my computer. Smarter AI targeting would be much appreciated. Instead of having the AI aim at where I am right now, have it aim at where it perceives I will be in half a second. Also, when an explosive weapon explodes (the shoulder slots), make it still deal area damage, instead of exploding and dealing no damage.
Pretty cool that there are 4 ways to win: closing the portal (capturing the evil graveyard, and having 15 soldiers available, takes 10 days), curing the zombie disease (researching everything at the laboratory, and then having 3 labs with at least 5 scientists. each scientist you add to the research will reduce the research time by 1 day with a min. of 10 days), drafting a constitution (capturing the city hall, and having at least 5 available leaders, which takes 10 days), and taking over every city block.
Okay at first...ends up being the same strategy over and over. Match armor I with spray gun, armor II with shotgun, assassin with sniper, special with frost gun, captain with acid gun. Upgrade as needed. Win.