Zombie Battle is a Free Zombie Game available exclusively at ZombiePrepKit.com

With modern technology
the ultimate zombie training programs are available
for any zombie prepper who seeks them.

From Notch, the creator of Minecraft comes a brand new zombie shooter called Shambles you can play for free!
Shambles

Plants vs. Zombies has an online free zombie game where, well…. as you might expect, you strategically plant a variety of plants to defend against the attacking zombies.
Plants Vs Zombies