when I was shooting muzzleloaders a lot we were always trying to come up with different stuff to make our monthly shoots a little more interesting,these are some you might try. cans of cheap shaving cream, balloons half filled with flour, a weight hanging from a half inch rope(see how many shots it takes you to cut the rope, a length of log chain strung between to points, small candy suckers or gumdrops on toothpicks at 25yrds. you get the idea! almost forgot the classic, a double bitted axe stuck in a tree with a clay pigeon on each side.