Thanks but I know what array is guys. I'm creating my zombies and pushing them into the array.
Specifically, I'm wondering what mil said here:
Do not add an ENTER_FRAME to each zombie.
Instead: iterate over the array of zombies you've got:
Do not add anythign to the stage, just add it to the document class:
Does he mean to add the event listener inside of the class of mcZombie? How can I do that if I need a parameter from outside of the class to run it, like the player's x-coordinate?