its nutty huh, they be running on all fours hella fast and shit. it gets intense after a while.
heres a tip i read in the walkthrough MTT
rotate people getting coffins, everyone will need the bait.
use bait SPARINGLY. only do so when its really needed and you have dynomite to trhough too
if you can, hold off on the casket until you killed most of the zombies, when you open one you get an extra minute on the clock.
pretty stratigic if you ask me