Carrion Feeder is the backbone sac outlet dork that protects my other creatures from exile removal, creates profitable chump blocks, and grows into a beatstick all on its own. I run as a 2-of, although I see some lists including 3.
Fume Spitter is great at taking care of problematic low drops, and with its cheap cost is easily recursive with TortEx to wipe out multiple creatures. I have 2 copies since my meta is quite aggro-heavy.
Spore Frog is such a powerful dork in the TortEx shell; it hoses aggro by being a recursive Fog effect. Helps enable the long-term grind plan. 2-of seems like the right number in the main.
Thoughtpicker Witch is alternative sacrifice outlet to the Feeder that shines more in control matchups or the lategame once your opponent is out of gas by manipulating their draw.
Perilous Myr is a dork that trades with creatures much bigger than itself, or can 2-for-1. Also can be sacrificed to a Feeder or Witch to shock a creature outside combat.
Satyr Wayfinder does double duty of finding that extra land drop for turns 3 and 4, and dumps stuff in our graveyard.
Wild Mongrel lets us get some early beats on while pitching useful stuff out of our hand. Also enables madness for cards like Grave Scrabbler and Arrogant Wurm.
Crypt Rats is the MVP against aggro and tokens, and with a buffered enough life total from our Golgari Brownscales and plenty of black mana, can end up being a wincon all its own. Some additional tricks; you can sacrifice it to Carrion Feeder in response to its ability on the stack, and you can activate separate instances of its activated ability in response to stuff like surprise pump or Doomed Traveler effects. 2-of since it's so powerful.
Stinkweed Imp is one of our two dredge creatures that creates the TortEx machine. By dredging the imp every turn we will always have pitch fodder for TortEx while also restocking our graveyard. He's a pretty nasty blocking flier in a pinch as well. I run it as a 3-of for consistency.
Tilling Treefolk is a neat utility creature that returns lands from our graveyard that we've dumped from dredging. Helps us hit our land drops, but also allows us to tutor up Ash Barrens for fetching, and Bojuka Bog against other graveyard decks.
Golgari Brownscale is our primary dredger, and the second cog in the TortEx engine. Dredging it does three things for us; it guarantees we get a creature to discard to TortEx, it puts a couple more cards in our graveyard, which means more TortEx targets, and it gains us some life, which is important since we're pretty grindy and we need to buffer ourselves against aggressive decks. Definitely a 4-of.
Grave Scrabbler is a sweet Gravedigger variant that lets us get tons of value off of TortEx. For , we get a bear and two creatures back from our graveyard. 2 copies included.
Horror of the Broken Lands is an easy creature to dump into your graveyard with cycling, plus it’s a pretty fantastic finisher. With Tortured Existence, a creature in the bin and another in hand, the Horror can get pumped +2/+1 for each black mana you can pay.
Arrogant Wurm is for the aggressive starts with a T2 Wild Mongrel into dropping it T3 (wait, I thought we're TortEx, not madness?). A 4/4 trampler T3 is not to be underestimated in Pauper.
Krosan Tusker is an awesome way to hit my land drops, plus I can discard a dredger with Tortured Existence with the cycle ability on the stack to get back the Tusker and get an extra dredge trigger.