I feel a bit late to the party discovering the whole custom doom wad scene only just a year or two ago, but I have managed to play through almost all of the most memorable and awarded wads that have been created over the past 2.5 decades by sifting through the Cacowards and highly reviewed wads from the archive. Grove easily takes the cake as my favorite custom doom creation, and possibly my favorite custom creation from any game I've ever played, be it Starcraft: Broodwar custom maps, Fallout mods, or any other content.
How the author managed to create such a sense of spooky ambience and wonder is really quite amazing. From the hand drawn automap, to the fantastic original music, and everything in between including even the quirky story and setting that B.P.R.D. seemed to think was silly; It all contributes to a great experience that every old school gamer should play through, although you might just need to leave your expectations of a typical doom wad at the door.
One downside to the original level was the fps trouble, but the alternate version eliminates the issue entirely while still maintaining the original feel (or by playing on modern hardware/source port). My only real issue with this version is the very difficult to find switch in the cave.
5/5, I love it, even in 2018.