Natural Snow Buildings. Drone/noise/ambient, but actually tolerable IMO. All of their songs sound like there's a non-zero chance a fucking demon will fly out of your speakers. They seem to be opposed to releasing music in a normal way and tend to just give CDs/tapes to friends that eventually reach the general public via file sharing. More recent releases have made it to Bandcamp in an official capacity.
Track Listing: 1. Invoke / Summon 0:00 2. Starless 9:24 3. Bone Diadem 19:04 4. Spells 25:48 5. Beyond the Veil 31:32 6. The Sixth, the Hand 41:24 7. A Proph...
As for most obscure I can think of: Discarded, an electronic artist. He did music for Million Dollar Extreme at one point, but I had trouble finding him even then. After a while I discovered he'd released albums and then went around the net getting them taken down. Even individual songs he released on SoundCloud get taken down or removed off of YouTube and other places. He rebranded recently under his real name, but even the albums uploaded on his official Bandcamp randomly disappear or change in one way or another. https://tristanleonidas.bandcamp.com/album/discarded
This might not be considered obscure within the standards of this thread as it features a cover of a not so obscure song done by a Ministry side project with early Trent Reznor. However, Ministry/NIN/Trent Reznor fans that don’t yet know of it seem to appreciate it so...
Armand Schaubroeck. Best known as the co-owner of the House of Guitars in Rochester, NY and their weird late night commercials from the late 1970’s. I had no idea that he made a couple of albums in the 70s. They're hilarious!
Most of the lesser known bands from MK Ultra Support Groups label are really good and I don't think most people know about them. Pacific Purgatory and Birdbath are two of my favorites. Reminds me alot of the Smiths for some reason.