how does one achieve this kind of sound? i'm especially interested in the settings/recording/mixing of the drum section, but any tips are welcome concerning this gloomy wall of noise!

http://www.youtube.com/watch?v=Ik4oNGK9cBE

Buy thick strings, tune to B or A (rather B) and buy a distortion pedal
buy the strings first as they are more needed
your welcome

It doesn't sound like there's much of anything unusual going on with the drums, the cymbals have a bit of analog roll-off from a lack of headspace, the snare is just a microphone aimed at a snare drum without effecting it much or at all.

I'm not positive on the guitars, but I'd guess that you could get a similar sound with an old JCM800 with the mids cut almost completely (0-1) and a tube screamer filling in that range, with a scoop around 1k hz and a sharp cutoff a bit lower than the drums in the higher ranges. Thickness of strings won't matter much, the tone here seems to be shaped by the distortion and mixing here.

At all costs avoid triggers! lol

I can tell you they are tuned to A, and as far as the tone, it has the Marshall characteristics with a healthy dose of I believe the Boss FZ-3 pedal. The tone is almost exactly the same as Electric Wizard's Come My Fanatics tone. Also, a lot of what you are hearing is bass. The bass is way higher in the mix than where most people would think to put it, and it is also heavily distorted. As far as drums, go ahead and do it with natural drums tracks, but you might have issues making the drums stick out from all that sound. If you want to trigger it, just take a kick sample that isn't too clicky, and go easy on the EQ.