Boss Attack - boss spaceship

This game's goal is to attack boss spaceship.
First, must avoid from boss' attack.
Let's avoid from boss' yellow bullet.
Your spaceship attack boss' spaceship by firing blue bullet.
Boss has health bar.
Must attack boss' spaceship till health bar is reduced completely.
Try your best by preparing, targeting, and firing.
Have victory by succeeding in attacking boss' spaceship.
Compare your score with other's in global leaderboard.