heres a useful tactic, when all of your upgrading is doen, pull all of the guys back into one door of the sport shop and build a new barricade there, the smaller chokepoint makes zombie killing easier for them, and when you need more ammo, molotov the zombies while they all scrounge
you could also just get a huge group of blue, yellow, or black ones, and use transform on thwm, if they turn red, use harvest (double souls), if the don't use vampiric touch (turns souls red)
that technique should give you a good bit of health if you set it up right, and maybe a little bit of luck is required
I love how I only found one grammar error in this entire game (to, instead of too)
usually games made at a similar quality level are full of them, which annoys me
it's one of those rare puzzles that is challenging enough to keep my attention, but not hard enough to make me look for a walkthrough (talking about pixel hunting and other unreasonably hard ways to make a puzzle harder)
 "I Remain"){kind=icon}
 "Luncheon Of The Dead"){kind=icon}
 "Arrival In Hell"){kind=icon}
 "Bloody Fun Day"){kind=icon}
 "Just add logic"){kind=icon}
 "Electric Box"){kind=icon}
 "Battle Fish"){kind=icon}
 "Mutant Uprising"){kind=icon}
 "One Shot"){kind=icon}
 "Age of War"){kind=icon}
 "Bubble Tanks Tower Defense"){kind=icon}
 "Paradox Embrace"){kind=icon}
 "Back to the Cubeture (1)"){kind=icon}
 "Hell Tour"){kind=icon}
 "This Game Needs A Mute Button"){kind=icon}
 "ALL Chuck Norris FACTS"){kind=icon}