I'm a software developer who has a taste for Doom modding.
This is a simple WAD to make the monsters in Doom2 harder and less predictable. It's meant to be played with ZDoom/GZDoom. It doesn't alter the player...
The zip file contains the full WAD with all the levels, weapons, and monsters. It is ready to play. Requires GZDoom (at least 4.3.3) to run. See README...
This is my work so far on my Zombie DOOM mod. It currently features six levels, modified monsters and guns.