since you're on abyssal, you have 2 options (or 1 i think), the greatest submarine of all time, the Barsuk and the ♥♥♥♥♥♥ Dugong....

You will be going for maximum pain this run, so Barsuk it is!

YOU WILL NEED A MECHANIC, UNDER NO CIRCUMSTANCES ARE YOU TO START WITHOUT A MECHANIC. Now, you may ask why the ♥♥♥♥ I said allat, well very simple, THE SAFETY HARNESS... This one thing is essential to your survival, noting that burns can do half of your health, second, you will be too poor to even buy a plasma cutter, no really, you will be broke after your first outpost

For the first outpost, it is advised to buy 2 of the SECOND engineer clothes as they reduce burns by 25% (you can also spawn with them if you want to), 3 fuel rods a ♥♥♥♥ ton of medications, specifically opium, and if you really want to buy ammunition for your weapons and or gun.

DO NOT BUY MORPHINE OR FENTANYL, THESE WILL END YOU AND I MEAN END YOU.

The only missions you should do should be transport missions, a single crawler can end your whole run, let alone a swarm, same goes for mudraptors. Do this till you get a third turret.

essentially what you have is a waiting game till the third turret, you also do not want to advance to the ahuehlioaaipumran ridge, otherwise you'll have a very fun time without a third turret

so, small recap:
- AVOID ENEMIES NO MATTER WHAT
- FIX ♥♥♥♥ ONLY WHEN ESSENTIAL
- GET THE THIRD TURRET
- DON'T HEAL YOURSELF IF NOT ESSENTIAL
- BE OVERLY CAUTIOUS OF ANYTHING NO MATTER WHAT
- ALWAYS HAVE ANTI-HUSK DRUGS
- DON'T LOOT UNLESS REQUIRED

when doing mass murder against the local wildlife, you must be VERY CAUTIOUS, take long deep breaths and run, never stay in one single place, when attacked, you must order your whole crew to fix ♥♥♥♥ except for like 2 people staying on guns, you will want to pray to jesus christ that the fauna is too retarded to go through the glass in your back

by this point, you're already either almost at your breaking point or going to kill yourself, thas just how it is! it'll get worse no worries

you want to prioritize hull upgrades and anti-deterioration for electrical mechanisms (or turret upgrades), the idea for this area is to get as much ammo and just upgrade your barsuk, save up till you can get either one of the orcas or an aziumututhtuhth

then for the rest of the game its simple! just go thru and live, hopefully you can use the advice given here to your advantage