Defense of the Solar System
The Solar System is growing fast and fast, more and more planets arise, to keep the solar system alive we have to keep eliminating some of them.
Rules:
1. The more linked planets in the same kind you hit, the high score you get.
2. Do NOT let the remain planet count exceed 30.
3. The planet arising speed will be faster and faster as time goes on.
You can compare your score with your friends through Game Center.