The Meat Grinder is the best weapon in the game by far. I am not taking constructive criticism on this take. It hits 3 times a turn and does INSANE bleeding damage. I don't care about the Sergal Spear, I don't care about the sword you get from Moonless, I could care LESS about the Sabbath, you JUST need the Meat Grinder. It will Grind all of your enemies, into Meat. You can combine it with Poison Tip to have it apply both Poison AND Bleeding, meaning that it can chew through bosses. The Platoon took like 5 turns with two of these bad boys. Sit down with me for a second. Let me tell you how to turn Fear and Hunger into Rip and Tear. Don't you want revenge on Vile? Don't you want to make the Death Masks crawl back into their graves at the sight of you? Don't you want to kill Father Hugo before he decides he wants to take his clothes off? Come with me. I will show you how.
In order to craft the Meat Grinder, you need the Weaponcrafting skill. This means you either need to play as Abella or you need to kill Abella. Luckily, Abella is a very good playable character. If you don't want to play as her, though, you have one of two options: you can recruit her, take her to the PRHVL Bop, and kill her before anyone gets there, or you can wait for her to moonscorch into Chaugnar. (Do NOT let her die while she's in your party; you will be unable to absorb her soul.) If you recruit and then kill Abella, you lose Henryk (and infinite free food) as an option, but you have a much easier fight and a powerful early party member. Chaugnar's a harder fight, but you can keep Henryk around. This really depends on your playstyle.
Once you have Weaponcrafting, most of the items should be easy to come across, except for the Bench Grinder. To my knowledge, there are only three of them in the entire game.
The first Bench Grinder can be found in Tunnel 1, in the Deep Woods. I cannot stress this enough: do NOT fight the centaur. It will instakill your entire party, it can tank booby traps, bear traps, and bullets, and it doesn't drop anything, not even heads. Do NOT fight it. Just run away from it. Once it starts running, it'll charge in a straight line for a brief time, so you can bait it into running at you and then dodge and it'll pause for a few seconds afterwards. If you aren't playing as O'saa, he'll be recruitable in the basement. Ask if he's alright, ask what his business is, tell him you're investigating the bunker, and say you either understand the tech or try to understand it, and he'll offer to team up. Or you can attack and kill him; he'll be weakened and won't bother casting Hurting in the overworld.
The second bear trap can unfortunately only be acquired from killing the mob. They spawn when you step on a set of tiles throughout the overworld, signaled by them throwing a glass somewhere in your direction. These guys are BEEFY and can chew through even a well-equipped party without much difficulty. In order to defeat them, I typically try to spawn them in Ruined Streets, isolate them behind walls, and shoot one or two of them to death. Target the Meat Grinder; he's the strongest because he has the weapon we're going to make. He'll drop the Bench Grinder, which you can pick up off of his body. Theoretically, you can kill him and then grab the weapon off of his corpse while leaving the rest alive. I wouldn't recommend this strategy. Once the Meat Grinder is dead, the rest of the Mob is MUCH easier to defeat.
The third can attained by using Steal while fighting Abella. Unfortunately, if you play as her, you don't have access to this one. I am so sure that I found one in the White Bunker on a recent playthrough, but I may be misremembering; I'll double check.
The rest of the ingredients for the Meat Grinder are easy to come across. You'll most likely collect plenty throughout the game. Just make sure you don't waste them on making a pipe bomb like I did...
Another satisfied customer!
Never before has there been a more game-changing item than the Salmonsnake Rune. (I mean, except for the Salmonsnake Soul from the original game. But that doesn't count.) This thing is crazy OP. Never again will you need to fear losing your arms to a Death Mask. Never again can the Woodsman menace you with his rusty axe. Never again will a Moonscorched villager infect you. Worry about rusty nails no longer! Not because you're not on Maso mode this time!!
The Salmonsnake rune prevents bleeding, infection, and most importantly, limb loss. This means all in-battle limb loss. Pocketcat's Gentle Dismemberment will take away a chunk of your health, but it won't manage to touch the limb. Magna-Medical will work but you'll keep all your limbs intact. Hurting won't hurt you.
This, of course, leads to an incredibly broken strat: get your party member with Magna-Medical (and it had better be Daan) a Salmonsnake Rune. Now they can use it whenever without losing any limbs!! Character death is still a threat, but a significantly less scary one.
Unfortunately, there are no guaranteed areas to spawn a Salmonsnake Rune. If you find one, save the run as quickly as you can. I've lucked out before and found one in the opening suitcases; I've also gone significant portions without finding one.