Ship Classes
Base ship can be upgraded to Blaster, Destroyer or Boat on level 10
Blaster, Destroyer and Boat can be upgraded to other ships on level 25
Tips
Shoot asteroids to gain skill points but watch out for exploding asteroids as those may destroy your ship!
In order to take out enemies, focus on improving your ship first and use exploding asteroids for your benefit. If there is an asteroids nearby an enemy, try to explode that asteroid.