World War Z

This one is pretty simple, but it's grindy. Just make sure that when you find a gasbag shoot them in the body (melee works as well) so the gas leaks and you simply throw yourself at it. If you headshot them without shooting at the body first they will die without leaking the gas.

If you start a private game, you can choose a Mutator that gives you more Special Zombies and less zombies.