This mod does one thing only: Adds a new ore block called Gunpowder Ore, which can be broken with a stone pickaxe or better to receive two gunpowder ore. It generates in large veins in both Dripstone and Lush Caves. If it's detonated in an explosion, it will create a small explosion as well.
This was created for one of my personal modpacks. I wanted a significant source of gunpowder but had removed all of the fantasy mobs, including the Creeper. The other mods that I found for adding a source of mineable gunpowder were more complicated than I wanted.