This is a mod that works either on GZDoom or Zandronum. It simply improves the looks of wall decals caused by blood splatters and bullet holes. I always hated how the standard blood decals looks like strawberry jam smears, and how bullet holes looks like black crayon drawings. This simple mod makes them more realistic.
It doesn't uses any kind of scripts, so it will work with any mod that does not uses custom decals. You can just put this straight into your skins folder and it won't cause problems with other mods. You can play online with it on Zandronum, and you can connect normally to other servers if they are not using this mod (only you will see the higher quality decals, while everyone else sees the default ones)
Keep in mind this mod won't add floor or ceiling decals because these are impossible without scripts.