Pistols only, no rebuys, no nades, add meteors, add lazers on several parts, double zombie hp and give them more speed, increase mother zombie ratio, double boss hp and increase the push attack, add a large bridge at the boss fight for zombies to cross easier toward humans, enable bhop just for zombies, give zombies warp and lure item from ff maps and all skins from skyrim (yes dp too).
no balls. we can do this. good challenge.