i got z+
but of course i dont know how a zombie would act in real world... but if it was like:
slow and quiet qhen at distance, and running and shouting when at a certain range (like 100m for ex.), if it could bring corpses back to life, didnt breath, sense living (smell, heat vision, many other ways..)and had no feelings, such as pain, or tireness. would be almost impossible...
the zombie model i used was like:
fast, but slower than a normal person.
dont feel pain, nor any other thing, but lacks on coordination and balance.
can sense livings.
eats anything it can chew.
have its flesh a bit softer than human.
and some things more...
BTW: i just spotted an error: Zombies are dead, They dont feel pain. in the Knife serrated/smooth it says about stabbing, but stabbing a zombie is useles, cuz the "stabbing" technic is used to caus pain, wich can make a living body to freeze due to it. but that can also be done with a toothed, but would cause more pain. but in this case, it depends a lot of the knife, and its tooths, a medium, leaf-bladed with "piranha-saw" tooths would be the perfect, cuz it wouldnt loose its cutting and slashing properties so quickly, and could be used for stabbing also, if you want.
i have some knowlege about knives, not proffessional