Im looking into the Shift Line Termofuzz for that kind of stuff and have pretty much decided on it but I havent bought it yet. What I particulary like about it is the crazier sounds you can get out of it (you can get regular fuzz too)
The Termofuzz is such a great pedal. I have 7-8 fuzz pedals right now and that one is possibly my favorite. It's just so unique and sounds great no matter how crazy you set it. It's a desert island fuzz if I ever met one.
The Pickle seems to be one of those pedals that people either love or just can't get to work for their sound. The reason being the EXTREME amount of low end it puts out. I mean like a semi truck load of lows. I've found that it's completely unusable for guitar because of that and some people don't like it on bass either. I love the sound of it, but it definitely has it's place. The way it distorts a low B can rattle walls.
To me that genre screams "muff".
Yes. +howevermany on muffs and clones/derivatives thereof. Great for the genre and there are a crap load of options of which particular pedal to get for that sound. It may require some research to narrow down just what you want. Tall font, bubble font, or black Sovtek Big Muff, EQD Hoof, Abominable Electronics Hail Satan, GR Hail Satan, and Hail Satan Deluxe, Black Arts Toneworks Pharaoh and Pharaoh Supreme, Vick Black Russian, Stomp Under Foot Civil Unrest, Earthbound Audio Supercollider, '71 Supercollider, and Beast, Solid Gold Electronics Imperial, etc. etc. etc.
The Duality sucks for that kind of thing IMO. I'd look at a muff or Megalith.
The Megalith is also a very very good choice. It's got the most saturation out of any other pedal I've heard and absolutely nails the doom tone. Unfortunately, the original Mountainking ones are rare and super expensive, but you may find one used or a good clone of one. If you google search "megalith clone" you may get a a Reverb.com listing in your results. That's how I found mine.
I also noticed someone (forgot to quote him) mentioned the Earthbound Audio Pale Mare. I'd put that somewhere in the same league with the Megalith in terms of insane amounts of saturation, although the circuits are totally different and the Pale Mare can get even crazier because of its noise gate (which you can decide to use or not - it has a switch). The gate makes it sound more synthy, but without it engaged, the thing just puts out a ridiculous amount of searing fuzz.