Defiance of the Fall
What happens if you stick a man in the woods with an axe and fill it with demons? You get Defiance of the Fall.
Progression-Fantasy
The Primal Hunter 13: A LitRPG Adventure
I don't know if it's the constant numbers going up, the MC always being able to win, or just the comforting voice of Travis Baldree, but I can see myself reading well over 20 books in this series.