Beautiful Doom is the grandfather of enhancement mods, born in 2008, updated multiple times, and finally updated again in 2015, after a long silence. Version 6.0 was an ultimate update that took it to the next level.
It's a mod that keeps original Doom gameplay unchanged but introduces lots of special effects and visual enhancements for deeper and more thrilling Doom experience. Practically every single object in Doom was remade and updated, and many effects can be controlled while using the mod.
Credits:
FrancoTieppo (http://francotieppo.deviantart.com/) for awesome Doom High-Def weapon designs that were used as a basis for weapon pickup sprites
* Death Egg - for all the really sweet HD item sprites