When someone says take over the world, what is it that first comes to your mind? As a hero, a villain, a politician, a pathogen? In this week’s app of the week, Plague Inc. by Miniclip.com, you play as a bacteria trying to start a plague across the entire world.

In the app you start off as a simple bacteria. As you progress, the plague will work itself to become a worldwide death machine. First you choose your bacteria type and a starter country to spread your disease. As you strategically use your knowledge of where you are to decide what to upgrade, the bacteria will continue to infect people worldwide.

You earn DNA which allows you to buy different evolutions. You will be able to upgrade how the disease is transmitted, where the disease is transmitted and defenses so the disease can not easily be treated.

The game has three levels of difficulty: casual, normal, and brutal. As easy as this game sounds, it is a challenge even on its easiest difficulty.

If you are into strategic games, then Plague Inc. is available for $0.99 on iTunes and for free on the Play Store.