The Zombie thing is easy guys. All u do is move ur arms in circles, while trying to stay away from the large groups of zombies and go through the gaps bewteen them ( Not small gaps ) and then go to the brains/meat things to get hp, although make sure there isnt to many zombies blocking you to get them. Oah and try to group them into a corner if the other corner has lots of brains/meat stuff so you can get it without taking damage.