Another ship will swoop down to you and fire a barrage of lasers. The graphics for this game are absolutely phenomenal. The explosions are very realistic-looking. The alien invaders are cleverly animated. Your Tank will pulsate on an off-blue color when your shields are up, and your Tank will generate an appropriate explosion when it is blown up.
Sounds are a mixed bag.
There is some techno style music in the background that I really enjoyed. The music sounds appropriate for the game, yet doesn't overpower you to the point that you want to shut it off. The actual in-game sounds are appropriate, but not anything to write home about. That is a very cool effect. Between each level, a screen pops up that previews the behavior of the new invaders that you will be attacking during the next level.