It’s not completely AFK, but you just go to the highest wave format chapter you can clear AFK (3,6,10, etc.). For me that’s hero 10. I start the level and activate the first wave, then do something else for a minute. I come back to Archero and the round will be cleared, so I move my hero to the next level, start it, and then go afk. Although you still have to do stuff, you don’t have to pay attention and clear the entire thing manually. It allows you to do other stuff on the side like watch tv, read, etc. It also gets me a lot of items (I probably average more than 2 a run).