I believe there is a mod which allows you to mine saltpeter, and I know there's a recipe for gunpowder that involves coal, sulfur, and niter. So while it can be dropped by Creepers, it is no longer exclusively a mob drop anymore.Wait, why is Gunpowder going into the Digger Backpack intentional instead of the Hunter Backpack? I thought mob drops were all supposed to go into Hunter.