I can predict what sort of responses I'm going to get in this thread, but I'll ask anyhow. I'm recording vocals for an upcoming black metal project, we're doing everything analogue and I was wondering the viability related to running a couple of effect pedals from the microphone to the PA.

I've recorded with other projects (digitally) and they would just put a little bit of reverb and a thin layer of distortion on my vocals during post but for this one we're recording live directly onto tape (dunno if that makes a difference). Recently we recorded a demo with the current setup and while it sounds alright, I wanted a bit more dissonance in terms of how my performance came out so I'm looking at two pedals primarily, one for the distortion and the other for the reverb. I'm seeing a bunch of vocal effects processors out there too that are out of my budget, running from $150 to $300+ that have shit on them i don't need like looping, etc.

tl;dr, is it worth investing in some pedals for (black metal) vocal recording/live performances or should i just not waste my time and do my vocals "clean"

If $150 for a vocal effects processor is out of your budget, you're going to be very limited in looking for two separate units for distortion and reverb within that budget. That being said, if you have a PA that doesn't have built-in reverb (that you like) and you want reverb on your vocals, get a reverb unit. You can probably find a used Alesis Microverb or something similar for $50ish, or you could invest in something a bit nicer - there's a lot of used rackmount gear out there and it's easy enough to do some research by googling it.

Distortion is going to vary more and depend on what you want it to do. It's more something you'll experiment with, rather than something you can easily find something worth investing a little bit of money in.

TC Helicon makes some pretty cool vocal pedals. I like to use their Double-track pedal to accent certain lyrics in songs. They're the only company I really see making traditional stomp box pedals for Vocals.