The game comprises ten levels, the story unfolding via text between levels, or the occasional in-game cutscene. At the beginning of most levels, excluding boss battles, players have the choice of picking either Kelly or Saburouta. Kelly's primary weapon is fast but weaker, and she's overall faster and more maneuverable. Saburouta is slower, has more limited maneuverability in the air, and carries a stronger primary weapon, the Matchlock Cannon. Basically the two characters make up the two difficulty settings, with Kelly being the "Normal", and Saburouta being the "Advanced" setting. The real difference being that Kelly's style allowed several lock-on targets, while Saburouta's weapon splashed and was aimed at specific targets. Because of this, Kelly's gameplay is more frantic and requires less direct focus, while Saburota required specific aiming and direct attacks to be effective. Kelly is also the only character to upgrade her gearskin.