5/5: Very good gfx, sound and atmosphere! Nice gameplay too. Some suggestions for the sequel: More maps please and make "hard" a lot harder. Use always the same weapon icons (ingame, upgrade screen, info screen).
Last map waves on hard (no. - from direction: S=soldiers, V=vehicle):
1 - all: few S
2 - top: some S, one V
3 - right: several S and some V
4 - bottom: some V, left: several V, left: S and V
5 - bottom: big group S and some V
6 - bottom: some V, top: some S and V, left: some S, right: several V
7 - left: some S groups, right: some S, bottom: some S, right: some S
8 - right: several V, all: some V, right: some S
9 - left, top and right: big groups S
I used 5 machine guns (entrance left, top and right for pulling fire), 3 snipers and 6 rocket launchers (4 at the bottom).
Winning the hard badge quick and easy: Build your city on a higher ground than your opponents. the size of your high plateau should be about one screen big. wait until you have 500 mana and drown them with a water storm or two. this works on every single map ^^
good game. my wishes for the sequel: more music, auto de-assign starting a day, auto assign at ending a day and a zombie button in navi bar (like food and survivors) showing zombi-free places.