This is a game about destroying the world. This is a long game. No, really. I mean LOOOOOOONG. 30 minutes or more. You start with a nice, happy, unsuspecting Earth. Not for long. You earn 1 point for every person who dies. The original baseline death rate for this game (the natural rate people die BEFORE you screw everything up) is 1 death/second. (a little more than in real life.) You can start increasing your points quicker by clicking the earth to trigger massive earthquakes. This is useful at the beginning, but becomes obsolete later on. As you may expect, you can send the baseline death rate figure screaming upwards to ridiculous and apocalyptic numbers like 5000 deaths/second. The way to do this is to buy Upgrades. They are the 6 squares on the left. You buy them once, and only once*, and it makes people die faster. Uh-oh. The other things you can buy are Disasters. They are the 7 rectangles on the right. You can buy these more than once. Each time you buy one, it kills a random number of people. It is often more likely that it will cover it's cost than not, but you can never be sure, so be strategic. Your goal is to kill all humans as fast as possible. There are 5 achievements to earn as well. See of you can earn all of them without peeking at their code. Be strategic, have fun, and destroy humanity!!! Congrats, by the way if you read all of this. This is a long instructions list. *With the occasional exception of Plague, which Humanity sometimes manages to cure, making you buy it again.
Credit to @InfectiousReindeer for boom sound you hear in atomic explosions, asteroid strikes and supervolcanoes! Credit to anyone who actually plays this game through to the end! It is a very long game! Please report bugs!