The first three Electric Wizard albums - Electric Wizard, Come My Fanatics and Dopethrone.
How it took me so long to listen to these I don’t know, if I’d listened to them at any point in the last fifteen years I would have been just as enamoured with them then as now.
Also, in a sort of similar vein: Forest Of Equilibrium by Cathedral.
Edit: And Earth 2: Special Low Frequency Version! I’ve owned Pentastar for 13, 14 years, yet never got around to listening to Earth 2 until a couple of months ago?!