I watched the first seven episodes of AMC's "The Walking Dead", season 2.
I really like Zombie flics, and this stuff is as good as they come. But one thing was getting more and more clear: Firearms are weapons of last resort in a Zombie apocalypse. They are simply too loud. You need silent weapons to make dead things deader (cudos to ZS for the cool motto).
Most Zombies in the show are disposed off with machetes, crossbows, rocks, even a screwdriver. Not very efficient, if you ask me. So I thought about how to make a more capable Zombie skull cracker. The solution: A hammer with a spike! But then again, what if you can't get the spike out of the skull fast enough to deal with the next undead attacker?
I devised a Zombie skull retraction lever. You can simply pull and the spike comes free. Works really great.
Also, I added a boule ball (what else) as a weight, but also as means to finish off the spiked Zombie. The force of the steel ball is unbelievable. And it is a great stabilizer for the slingshot!