This is a very simple mod that increases the health and damage (that they do to you) of every mob based on how far they are from origin (0,0,0). This means that as you go up, down, or out, the same mobs will be tougher to kill and more likely to kill you. By default, they'll be five times as tough at the edges of the map.
Obviously, there are lots of better ways to make a mob tougher, but this has the advantage of working automatically and effortlessly. It's also simple to scale up if you add an armor mod and realize that combat is now much too painless.
This mod ONLY works with mobs redo.
The source is available on github.
Mod dependencies: default, mobs_redo