Make sure you ALWAYS have a shotgun to take care of those zosmbies.
BTW on level 78 you have to kill the zombie on the top left corner and he'll drop the neglector.
take it and blast the gate, take a disruptor cannon and start killing all the zombies, then jump out of that place.There will be a helicopter, just dont go in it. if you do you will be killed when it crashes. instead take the left, fight all the way until you reach a gem. then watch the cutscene
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