The AJ-37 Viggen's Metal Storm isn't very strong with no power-ups, but even one turns it into a formidable fighter. The special weapon Thor Hammer sends out several large enemy-seeking missiles; however, unlike with many other special weapons in the game, the player is not protected while Thor Hammer fires. Therefore, it is a difficult weapon to use successfully.
The AJ-37 is now strong even without power-ups, and it reaches full power very quickly. The special weapon works the same as before, sending out several missiles which automatically lock onto their target.