A fun game using Palladium's house system. It assumes that the zombie plague has already happened and you're playing in that world.
It could also be played in the world before it fell apart, quite easily.
The game uses a d20 roll high to hit, defender may dodge or parry. It's not a terribly complicated system, but it is showing its age. Skills are done with a % like the BRP system, equal to or less than the skill number. One can modify one's stats with skills, so that's a nice little bonus.
A wide variety of character classes are available ( it's a class and level system). One can be an ordinary person, a Shepherd of the Damned, Reaper (biker gang member), Hound Master (works with dogs), Scrounger and Soldier. Even a Quick Character creation system to get into the mayhem in a hurry.
Besides the terrors of the undead, there are other villains, Death Cults (who worship the undead)
A wide variety of zombies to throw at your players, even the half-living, which can be quite interesting take on the genre. There are the standard shamblers, runners, crawlers, thinkers and more. Lots of variety to keep players guessing. Some rules regarding the difficulty to kill a zombie are not to my taste, but that's fine, it's easily modified to suit my group.
The layout is different, with a majority of the rules at the back fo the book. It takes a bit to find out where everything is located. I put small tabs on my harcopy version, just for ease of navigation.
As a standalone product, it's quite complete. Lists for equipment, scavenging/scrounging and vehicles round out one's options to equip their character.
There are 101 adventuring ideas to get your group started. Rules for scavenging, zombie hordes .
The game is easily house ruled without breaking it.
The supplements expand on the world and offer even more creatures, locations, ideas and adventure.