By the way, kind of an annoying glitch, enemies around 40+ levels don't give as much as 30-39 enemies for some reason, I'm getting 1000-1100 from 30's and 300-400 from 40's
7 or 8 squares left to reclaim, somehow 964 zombies, all overrun, could not even bring one of them down to infested, got 25+ people killed trying to take them back...
Got a glitch where I had 1 survivor left and the "Today's Results" kept saying people that were already dead died, it happened 4 or 5 times, then I died =/
Tip: Just because you have cleared the zombies in a square, doesn't mean you should reclaim it, (especially on nightmare mode where zombies are always surrounding your base) pay attention to the number of surrounding zombies, it's key to not being killed every night in an attack.