For an in-depth analysis of the archetype:
https://www.mtgvault.com/theswarmer/decks/tortured-existence-essay/
The conditions that a TE deck must meet:
1. A TE at all times
2. A yard with answers to the current situation and a means to reach more answers
for future situations.
3. To live to set up 1 and 2
4. To re-setup 1 and 2 after being hated on in games 2 and 3, hell, or even 1
So Gush got banned, and the meta didn't change for a while. Then AA came out, and threw the metagame for a loop. The result is something much less desirable than the post-ban metagame of Burn, UR delver, Elves, Stompy, Boros, and Tron.
This version is built to compete in a brave new world which is home to the following as of 1.8.19:
Jeskai Snow: This midrange deck attempts to win with flyers, in a manner that is however slower than that of Delver decks. Thus making it a better matchup than delver usually was. The way we deal with this deck is firstly with Deadly Recluse and secondly and obviously with a greater number of Stinkweed Imps. The deck is a slow midrange deck and thus a good matchup for the most part, the main problem comes from their ability to tutor Relic of Progenitus, often as soon as game one. Caution when dredging is thus advised as most losses will be attributable to skill and luck surrounding relics.
Tron: Argh, it is one of our worst matchups. It is the reason we maindeck a Thrull Surgeon. We can't race it, all we can do is out-pace it. Meaning that if they are running the variant with a playset of Ghostly Flicker we almost can't win. Our strategy - no matter the tron variant - revolves around ensuring our Crypt Rats can disrupt their flickering, that Brownscle can ensure our survival. That essentially means we lose in game 1 almost all the time. In games 2 and 3 we will need enormous amounts of luck, graveyard hate in the form of Macabre, and loads of Surgeons.
Keep in mind that the traditional approach of Feeder + Fiend is much better than Surgeon against Tron. I chose to optimize this against other decks.
TLDR: there are worse things than death, Tron for example.
Stompy: This matchup always has - and likely always will - revolve around Rats and Frogs. Very little else matters. Games 2 and 3 should be easy however due to us running 3 Frogs, 3 Rats, and 1 Gnaw.
Affinity: Another reason to run 5 deathtouch creatures. This matchup has historically made up for a large portion of the reasons why I have been advocating good early game blockers. This matchup is either won by blocking with threats of sufficient size or ability, or with a long string of chumps leading into a big Crypt Rats turn. Whatever happens, Brownscale is your best friend, as most games are in fact lost to a 40 damage fling.
Burn: It all comes down - as it always has - to brownscales, the matchup is good, mulligan intelligently and you'll win.
Elves: The recipe for victory is one of rats and frogs, once again. It's a good matchup, though usually a boring, draw dependent one. The skill in this matchup is mainly relegated to one's ability to maindeck and sideboard correctly - it's a game of odds, you are trying to improve your odds of wiping/locking them whereas they are trying to maximize their odds of not getting wiped/locked. Whoever draws better wins so long as neither player drank heavily before the match began.
An attrition deck for all to behold, Tortured Existence is theoretically capable of grinding out any pauper deck. The issue most often inflicted upon it by misguided if well meaning deckbuilders is planning for everything, which is simply impossible. Including Mesmeric Fiends and Carrion Feeders would add about 20% to our Tron matchup, but subtract about 30% from our matchups against all ground-based creature decks.
The goal each game is to be planning 3 turns ahead, know your deck - as well as that of your opponent inside and out - and to slowly build up a sufficient amount of incremental advantages to where you're virtually unstoppable.
Should a TE be nowhere in sight, probably hanging out somewhere with your dreams and hopes, your deck can still function, thanks to the abundance of discard engines and Scrabbler copies.