Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode. 
 
- Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way. 
 
- Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill. 
 
- Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy 
 
- Drop points into your rig's HP early 
 
 
Any more suggestions?

I finished it 2 days ago, so here's my advice.
 
1) Carry only 1 to 2 weapons. You will rarely ever run out of ammo this way, as most loot in the game is randomized depending on what weapons you currently have equipped.
2) If you are playing the Xbox 360 version, the game will create a temporary save at Chapter 7. If you die and choose to "Continue from last Hard Core save," you will restart there. However, if you turn off your game, exit your game, or choose not to continue, you will lose this save.
3) On the subject of saves, I saved at chapter 10, 13, and 14 (near the very end, at the entrance to 15).
4) Carry one to two stacks of Stasis Packs. Although I rarely used Stasis, it's important to have in the case of an emergency.
5) For the final battle, I suggest grabbing the Force Gun. It will deal with the Pack Shades in one shot.

I never purchased health until near the end of the game, but always carried 4 packs of whatever was the strongest at that time. Any extra that I found I placed in the safe for later. I did, however, always purchase a large amount of ammo (at least 100), simply to make sure I never ran out. At the end of the game (chapter 12+), I began carrying 200 rounds of ammo, and actually, I ended up beating the Elite Brute with only 3 ammo left (so I'd suggest carrying a bit more than that, obviously). With all of my extra money, I purchased power nodes.
 
For upgrades, I went like such:
1) Upgrade RIG for 2 nodes of HP
2) Upgrade Stasis Module until I got full energy
3) Upgrade Plasma Cutter until I got the Special (+fire damage)
4) Go back to my RIG and upgrade the rest of the HP
5) Finish Plasma Cutter
6) Finish Stasis
 
The duration of Stasis isn't a big deal until later in the game (specifically chapter 14 and 15 when you fight the regenerating Necromorph), so you don't need to worry about upgrading it too quickly. If you purchase power nodes with all of your extra money, you'll be able to max everything out well before the end, and then can simply focus on ammo and health.

This thread is gonna be very useful when I begin my hard core playthrough.

I just beat it today so here's my tips/thoughts. Final clear time was 5h 48 mins, I was quite surprised by that. Anyway...
 
1) Always store excess ammo/health/stasis packs in a shop. It's worht the time to backtrack to one, near the end of the game I didn't need to buy much as I had so much saved up.
2) I only used the Plasma Cutter and Ripper. Only go for damage and ammo upgrades, important to note that upgrading a weapons capacity while it's empty will give you a free clip of ammo.
3) Buy the Contact Beam ASAP and sell all of its ammo. They fetch 1k per round, you should never be really strapped for money if you constantly do this. Also, upgrade its alt fire, I found that a godsend for the final fight. Stasis mod is excellent. 
4) Upgrade HP on the RIG and no. of shots for stasis. Stasis and the Ripper make a lethal combination, you can easily take out 3 or 4 enemies with one shot this way. Really helps conserve ammo. 
5) The power node rooms are always worth it. Some even have a node in to replace the one you used.  
6) You can really abuse melee and spike shooting in the early parts to build up a good supply of ammo and health fast. Don't use the stomp though, simply shoot off a leg then look downwards and punch them, it's got far less recovery frames.
7) Always make sure you equip the vintage suit when you buy anything, over the course of the game you can save a lot of money through its discount. 

Wait a month. EA will sell an all weapons and unlocks pack soon enough.

 Main places I came a little unstuck (in story order) were:

• Laundry room
• Upside down train bit
  
• The church bit
• Bottom floor of habitation (3 fat duders and 6 fast tail duders)
• The second raptor type duder encounter
• The part with the canisters and tentacles
• The first hallway of the Ishimura
• The decontamination room
• The bridge of the Ishimura
• Most of the mine section (especially the lift ride)
• The drill ride
• Just outside government sector
• EVERYTHING after government sector (most notably the 3 red rooms and the gauntlet at the end)

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

" @Akeldama said:

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

I'm going to be honest, that sounds more like advice suited for Zealot, not Hardcore. Hardcore uses the survivalist difficulty, so running out of ammo really shouldnt be a problem until later in the game. The last thing in the world I would want to happen is to lose 3-4 hours of progress because I was trying to save some ammo, then get mugged by another necro when I'm trying to melee the stasised one. Definitely would recommend using the 2 shots to a leg, run up and stomp method. Saves the 3rd shot on the slashers and spitters. Also, I found using limbs to be pretty useless except in the case of the exploding armsack guy. Things happen way too fast in this game to be searching around for limbs in the middle of a fight. "

Hardcore mode = complete.

Bookmarked for my attempt. 
 
Wait, so Hardcore isn't at Zealot difficulty?! Doesn't seem so tough now that I know this. I'll probably be kicking myself for saying that before too long.

" @sixghost said:

" @Akeldama said:

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

I'm going to be honest, that sounds more like advice suited for Zealot, not Hardcore. Hardcore uses the survivalist difficulty, so running out of ammo really shouldnt be a problem until later in the game. The last thing in the world I would want to happen is to lose 3-4 hours of progress because I was trying to save some ammo, then get mugged by another necro when I'm trying to melee the stasised one. Definitely would recommend using the 2 shots to a leg, run up and stomp method. Saves the 3rd shot on the slashers and spitters. Also, I found using limbs to be pretty useless except in the case of the exploding armsack guy. Things happen way too fast in this game to be searching around for limbs in the middle of a fight. "

Wait it uses survivalist? I thought it was zealot difficulty, maybe it won't be as bad as I was expecting, except for the 3 saves thing. "

" @kerse said:

" @sixghost said:

" @Akeldama said:

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

I'm going to be honest, that sounds more like advice suited for Zealot, not Hardcore. Hardcore uses the survivalist difficulty, so running out of ammo really shouldnt be a problem until later in the game. The last thing in the world I would want to happen is to lose 3-4 hours of progress because I was trying to save some ammo, then get mugged by another necro when I'm trying to melee the stasised one. Definitely would recommend using the 2 shots to a leg, run up and stomp method. Saves the 3rd shot on the slashers and spitters. Also, I found using limbs to be pretty useless except in the case of the exploding armsack guy. Things happen way too fast in this game to be searching around for limbs in the middle of a fight. "

Wait it uses survivalist? I thought it was zealot difficulty, maybe it won't be as bad as I was expecting, except for the 3 saves thing. "

I'm not 100% sure, but I saw it mentioned a couple times in the neogaf thread. "

" @kerse said:

" @sixghost said:

" @Akeldama said:

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

I'm going to be honest, that sounds more like advice suited for Zealot, not Hardcore. Hardcore uses the survivalist difficulty, so running out of ammo really shouldnt be a problem until later in the game. The last thing in the world I would want to happen is to lose 3-4 hours of progress because I was trying to save some ammo, then get mugged by another necro when I'm trying to melee the stasised one. Definitely would recommend using the 2 shots to a leg, run up and stomp method. Saves the 3rd shot on the slashers and spitters. Also, I found using limbs to be pretty useless except in the case of the exploding armsack guy. Things happen way too fast in this game to be searching around for limbs in the middle of a fight. "

Wait it uses survivalist? I thought it was zealot difficulty, maybe it won't be as bad as I was expecting, except for the 3 saves thing. "

I'm not 100% sure, but I saw it mentioned a couple times in the neogaf thread. "

" @sixghost said:

" @kerse said:

" @sixghost said:

" @Akeldama said:

" Lets make a go to thread for anyone foolhardy enough to attempt this hellish mode.  - Stasis is your best friend. When in an area with a stasis recharge station, use stasis and melee your enemies. You will conserve a ton of ammo this way.  - Obviously, use the dead necromorph limbs as weapons. Two hits with a limb is a kill.  - Plasma Cutter is the way to go. Min max your ammo drops by keeping this weapon with you and selling off other more useless ammo to buy plasma energy  - Drop points into your rig's HP early   Any more suggestions? "

I'm going to be honest, that sounds more like advice suited for Zealot, not Hardcore. Hardcore uses the survivalist difficulty, so running out of ammo really shouldnt be a problem until later in the game. The last thing in the world I would want to happen is to lose 3-4 hours of progress because I was trying to save some ammo, then get mugged by another necro when I'm trying to melee the stasised one. Definitely would recommend using the 2 shots to a leg, run up and stomp method. Saves the 3rd shot on the slashers and spitters. Also, I found using limbs to be pretty useless except in the case of the exploding armsack guy. Things happen way too fast in this game to be searching around for limbs in the middle of a fight. "

Wait it uses survivalist? I thought it was zealot difficulty, maybe it won't be as bad as I was expecting, except for the 3 saves thing. "

I'm not 100% sure, but I saw it mentioned a couple times in the neogaf thread. "

On TNT, Dino himself said it was Zealot.  "

  Hardcore mode is presented as the toughest difficulty mode in the game. However, the description is quite misleading. All ammo and health pickups are lower than usual but the enemies in the game are the same as they are on the survivalist difficulty.

Bookmarked this thread. Going to attempt hardcore this weekend. Looking forward to it.

So having beaten this I will now give you the best advice I have, first don't die. Having died once at chapter 1 and never again after that, if you are careful enough it is possible. If you are dreading an encounter, hang near the door and back up as you need to, it makes most of the encounters that I feared easy as hell. Also in the last three levelled red room, use the detonator as well, it makes that encounter easy as pie. Play through the encounters that you are about to get to on a second save first so that they are fresh in your mind. End boss I beat with the force gun and used the contact beam on the marker, made it really fast and easy, only one wave of pack.

To those who beat Hardcore: Where did you save and where do you think I should be saving? Should I make use of the Chapter 7 disc-swap save? What I was thinking was a save at Chapter 5 (so I can quickly redo the one-hit kill sequence with the Tormentor), then the disc swap checkpoint at chapter 7, then chapter 10, then chapter 13. How does that sound? 
 
@big_jon: Where did you put your power nodes first and what gun did you use through the game?

Stasis and health, then the plasma cutter and pulse rifle.
 
I used the Plasma cutter, Pulse rifle, Detonator, contact beam and lastly the force gun.

I haven't beaten hardcore mode, but I did beat zealot, and alls I got to say is get that contact beam and upgrade to the stasis special alt ability. It will save your ass and your ammo in the endrun. If you get surrounded just pop that contact beam into the floor and watching everything fly back in slow mo and book it to the marker. Don't get fixated on eliminating all the enemies till they stop spawning since you have the regenerator to worry about and the enemies are more trouble than the possible items or money they drop. For the red balcony rooms in chapter 13 I just run for it, too many damn enemies spawn in that it's better just  to stasis/contact beam any that pop out and run for the bottom level. Hell I spent most of the last chapters running. But I was on zealot so who knows what's a better strategy.
 
For hardcore what's the ideal armaments? I'm keeping my zealot force gun and going to upgrade the contact beam. Gonna keep the plasma cutter as well I suppose. For me it's a toss up between the seeker rifle and the pulse rifle. Seeker rifle can take out those tentacle babies real quick. And those tentacle babies fucked me up in the later chapters where I'm on the drill and when I'm hacking that big door in Government sector where all the necros flood in from the hole that you use to drill there. Projectile enemies are the ones that are going to fuck up my run, I just know it. Damn pukers and their slow down vomit shit, those things that fling spikes at you in zero g, spitters, lurkers, and all kinds of shit. Don't really need the detonator since I know where all the enemy placements are and stalkers are easily dispatched with the force gun, just wait for em to charge.

I just beat hardcore mode and here's another tip. Once you get the vintage suit, stick with it to the end of the game. The discounts are more than worth it imo. Spend that 36000 credits on nodes and ammo and health packs instead of the advanced suit. Also try to restrict node upgrades to damage only, really the only thing worth while in a hardcore run. For the force gun you may need to upgrade speed, reload, and damage. For contact beam, go for that stasis upgrade. That thing will save your life in the final chapter.

 I'm on Chapter 9 in my Hardcore playthrough, would have kept playing but I have class tomorrow. I've died six times in the course of the game and have used two of my saves (meaning I have one left).
 
Upgrade Stasis, max out duration 
Upgrade Plasma Cutter, ideally maxed out 
Upgrade Rig, Health and Damage are very important o2 is not 
Save as much money as you can to stock up on health and ammo when necessary  
If you're playing on a console with the two discs, you get a free checkpoint after you are prompted to swap discs
 
Best advice I can give, be prepared to get angry and die. Don't go in thinking you'll get a flawless run, it is foolish. Hardcore mode is all about learning where enemies spawn and the various points and tactics you'll have to use to survive.

I'm up to the end of chapter 5. Not sure if I should use my first save, I'm afraid that I will fuck up the tormentor part. Anyway, so far it's been fairly easy. After dieing once in the really early goings, I've been doing fine. Barely using any health, already have all damage upgrades on my cutter plus the special and a few on the way to those. Two health upgrades as well. The enemies seem weaker than Zealot, but a drops are on par. Also carrying around the force gun, but haven't used it at all yet. I have to collector's edition suit, so I'm sure that helps.
 
Not to bad at all so far. Just not looking forward to the end game.
 
EDIT: Ok, I'm going for it, not going to save until the second disc. Nerves are up.
 
EDIT 2: Great success!

Just died and have to start over :(

" @Zaft: How do you deal with combat? I just finished Casual and there were spots where things just kept coming at me from all angles. I've heard people stressing just backing yourself into a corner. Is that basically the trick? "

I'm very close to beating Hardcore. It's been a frustrating experience. At least I can say I've been building character.  
 
Anyway, here are some tips for Hardcore.

 
First nodes should go to the first 2 health upgrades. 
Max out Stasis' energy for more shots.  
Upgrade the cutter's damage and ammo.  
 
Other than the cutter I relied solely the contact beam and pulse rifle. So I upgraded the contact beam's alt fire to stasis. The pulse rifle was around only for dealing with the toddler necros, a group of annoying mini ones, and to grenade the guardians sticking out of the wall. The alt fire of the contact beam makes the mining elevator sequence way too easy.  
  
Memorizing spawns and strategies are a must. Stasis often and well. Aim for the legs. A lot.  
 
As for my saves, my first save is right after the solar array, the second is right before mining drill, and my last save is right before the eye poke machine.  
 
I figure I've have it beat by tonight or tomorrow.  

So far I'm using the plasma cutter and the line gun, that alt.fire on the line gun is too useful. 
 
Used my first save at chapter 10, died a few times during 1-6 to stupid stuff came very close to not bothering because I was so tired of the intro.

Watch a playthrough on Youtube as you play it. Know what's coming up next.
 
AND FORCE GUN. Parts that I thought were going to be hard, were manageable because of the Force Gun.

I beat it last night.... whew. It was nerve-wracking and exciting. The thought of dying and losing a few hours of progress was killer.  
 
I used the Plasma Cutter and only the Plasma Cutter (fully upgraded) except for the the final fight which included the use of a Contact Beam with the ALT upgraded fully. 
Upgraded Rig and Stasis. Never had to much trouble. Anytime I felt overwhelmed I used stasis and took a step back. I found holding one weapon meant mainly ammo 
for that one weapon was what enemies dropped, leaving me with, for the most part, plenty of rounds. Health was surprisingly plentiful.  
 
Impale, Impale, Impale. I highly suggest getting comfortable with killing enemies with stasis > cut off limb > TK impale. Most killed enemies will produce at least 1 or  2 impale  spikes just by TK-ing their corpses.  Aiming for the legs seemed like a last ditch effort for me because you still had to shoot them or stomp them while they are down, which wasted more ammo and ran the risk of getting hurt. Spiking someone meant less shots and pushed back any attacker far enough to re-evaluate the situation if they didn't die from it. Upgrading DMG on your Rig will make your TK thrown objects more powerful. Watch out for Cysts but don't waste ammo, impale or trick em into killing themselves. Red rooms in chapter 13 can be easily ran through, stasis and run was all I did through the last few chapters.  Contact  Beam ALT fire the last boss. Kills the Pack,  pushes her back, and damages her as well. Once the marker opens switch to Plasma and fire a few rounds, repeat. Watch out for the instant death when flying to Ellie's ship (just avoid hitting stuff).  
 
Saved at 5, 9 (before the Stalker warehouse) and 13 (before the blackout)