This is a game that may be compared to The Legend of Zelda, though more linear in it's game play. The game is broken down into many stages, the goal of each being to simply find a way into the next stage. Playing out in puzzle fashion, you will shoot all the enemies on screen, earn the hidden key, and find the correct exit. Defeated enemies will randomly drop bonuses that can be collected; these items include health restore, increased armor, and weapon improvements.
Beating the entire game requires successful progression through 125 stages.