If its one of your first games, its decent. Clicking is a bit glitchy and I myself am not a big fan of the theory of the game, but still as I said it's a decent game.
I think that you could use this as part of a bigger game where either you have to think about not eating many zombies but having alot of food or eating alot but not having that many humans, or my other idea would be an endurance mode where you want to make as many zombies and then try to take over the world.
Can I get help on level 9. And it its a very good game if you enjoys thinking pretty hard but it seems like Proffesors Laytons Something DS game the solutions are all very simple but appear hard.