The Purge

The Purge is your main objective. It's progress bar increases as you eliminate Aliens from the planet.

Once it is completed, you have eliminated all the alien life from the planet, and won the game.

If your progress returns do 0%, you don't lose the game, but you are as far as possible from your objective.

How it works
Each combat expedition you successful complete, increases the Purge's progress by 1%, but this value can increase based upon the type of the expedition: The progress can also rewind, and decreases each time your explorers fails in a expedition and can't flee.
 * Captain Base - Advances in 5%
 * Commander Base - Advances in 10%
 * Alien King Base - Advances in 30%
 * Captured and/or killed explorers decreases The Purge's progress in 1%