If the game freezes, just click inside it (games can get unresponsive if you click elsewhere on the page).
In this 3D game with great graphics you can enjoy destroying zombies. They will come in groups, every next group will be more and more dangerous. In addition, you do not have enough cartridges, but you can get more if needed. Just go to the specific icon and wait there for 10 seconds. You can do the same thing with lives. Try to hold out as long as possible.