Sometime in the past, the people of the country of Parts had found a way to become immortal, but only with elderly nobles. Five of these elders, Ballossum Pench, Gabriel Hammer, Jimchuck Spanner, Olsorro Slasher, and Leonard Drill, obtained immortality, and became known as the Motoruin sages. Their newly found power let them to revolt and start taking over the Parts kingdom to start a new world order, collapsing the government and destroying parts of the country in the process. As their plans unfold, five children of one of these villages decide to battle the Motoruin using another new invention: the semi-automatic propelling engine, known as "Progear".

A horizontal shoot 'em with large amounts of particles and bullets on screen almost at any time. Animations and graphics are lush and vibrant with a high sense of detail and artistic flair. Take control over a steam-punk engine called "Progear" and wipe out anything in your way to take down five elders who believe they've found a way to become immortal.