Most games that have a zombie apocalypse or The Walking Dead type theme you're the humans trying to survive. And while that's fun, we've seen hundreds of those games. Plague Inc is something completely different.
Instead, you are the plague, and the goal is to infect and destroy humans, not try to run from the deadly virus. You must infect and kill as many people as possible in each location or level, which is pretty interesting.
The game has an infectious user interface, fun graphics, and challenging levels that get more difficult as you go. So, download the game, go offline or on vacation, and take out an entire continent of the human race.