100 Aliens - Difficult Puzzle

100 Aliens is a simple and addictive puzzle game with retro graphics.

You have to eliminate all the aliens off the grid starting from where you want and then moving horizontally, vertically or diagonally under the rules of the game
Legal moves are indicated by colors, so that you focus on choosing the best alien to kill to be able to chain them all. Each color has a meaning to help you in your decisions.

The rules are very simple and the games very quick, but to eliminate all the enemies is not as easy as it looks. You will surely need many tries before you get to beat the game and save the Earth from invaders ;)

The game provides several levels, but the real challenge is to overcome the full grid of a hundred aliens.
If you like games of thinking with simple rules and high difficulty, like solitaire games or puzzles, 100 aliens will quickly become addictive and you will enjoy a quick game on the subway or waiting for the bus or train.

Will you be smart enough to defeat the hundred aliens?