I sometimes do "modern" black powder hunting for whitetail. I've got a .50 caliber in-line muzzle loader. I use 777 pellets, power-band bullets and 209 primers for ignition.
It's still "simple" but probably in a different way than what you might get with an old flintlock or something like that. It's a lot of fun and, like you said, a bit of a challenge (more so than with a shotgun or rifle, less so than archery). You have to be 100% sure of your shot because there is no opportunity for a follow up shot. Well...usually. I've dropped a deer with it before and it's friend that it was having lunch with hung out for a while longer.