While practicing in the back yard I put some bird seed on top of one of my targets with another target stop behind it. Kind of set up like a stair step. Over the summer I got 3 chipmunks and 4 grackles with this set up. The best of the shots was at about 28 yards and I called for a "heart " shot. lol Took his heart, lungs and both front legs. lol I must have tried 50 shots at the grackles before I figured out to lead them a little, expecting them to fly.
The most difficult kill IMO is a turkey with out using a blind. I'm 1 for about 100. lol I've gotten to full draw maybe a dozen times and only got 1 shot off but it was a good one. I thought I was going to get number 2 about 2 weeks ago but I swear this Tom could see though trees! lol He walked behind a great big tree, I drew, he flew. I find it hard to believe that he herd me draw so he either saw through the tree or he saw my shadow somehow. Without a blind or good cover, just getting drawn on a big tom is tough much less actually getting a good shot off.
I know a guy who killed a chick-a-dee with his bow string. He was at full draw on a doe, a chick-a-dee tried to land on his arrow, right by the vanes, inches from his face, freaked him out, pulled the trigger and he said it exploded into a bunch of feathers in his face. At least that was his excuse for flinging an arrow and missing a doe.lol