Takeshi no Chosenjo wins this category!

I'm fine with games being difficult (challenging), as long as you get the feeling that you are making progress and becoming better tackling the obstacle with each retry.

If it just feels you are constantly banging your head to the wall and not really being any closer to beating some obstacle (or you feel it is based on luck, like sometimes you are close to beating it, but the next 10 retries you are far from it), then it is just frustrating.

Adventure games actually frustrate me often if I don't seem to have any idea how to progress with some puzzle, no matter what I try. Then I read a walkthrough and find out there was some very obscure and rather illogical solution, or even some item I didn't find in pixel hunting... Hence adventure games are not really my favorites, even though I used to love e.g. old Sierra and Dynamix adventures.

Also, what you mentioned about having to replay from the beginning of the level if you die in Volgar (I haven't yet played the game)... I also feel the game shouldn't position you to constantly replay the boring parts, just in order to get to the difficult part where you keep failing. Hence I prefer save-anywhere, but predetermined save points are fine too as long as they are

Agreed, assuming you consider "the game should be fun" to be a fundamental rule of game design.

Demon's Souls kills you right away from the beginning by putting you, at LVL 1, with 0 experience, against a huge and powerful boss.
Fun thing is that, with enough patience and reflexes, if you are already used to the mechanics and start a new game, you can ACTUALLY KILL the boss, even if it takes forever, and by doing so you can then confront the final boss of the game who proceeds to royally kick your ass by KILLING YOU ON THE SPOT ANYWAYS.

Another good example is in Summoner, where it serves as a mean for a plot twist, in a very clever and immersive way (i won't spoil it).

There's also a particular puzzle in Machinarium that is pure genius. Usually point-and-click puzzles are either logical (the good ones) or illogical (usually bad designed ones), but this particular one is PURPOSEDLY ILLOGICAL, promoting lateral thinking (again, i can't explain any further or i'll spoil this part of the game).

LOL, are you serious?
How old are you? Most classic arcade games, like for example Ghouls n' Ghosts, Contra, Ninja Gaiden, Battletoads, not to mention the whole bullet hell genre, classic point-and-click games like King's Quest, old school MMORPGS with permadeath, rogue-like games, the AI on fighting games like KOF or Mortal Kombat II and many, many, MANY more were way harder than those titles.

The Souls series is particularly a bad example from you, because the games aren't easy but they are very very fair, even if compared to the "hardcore" difficulty level of most contemporary games. You basically never die in Souls games unless you make a mistake, which can't be said of several other games. And they even allow you to resurrect, good luck doing that in a rogue-like.

Obviously if your standard is games like Assassin's Creed, those may be seen as hard, but they are not. It's the other way around. It's just that most games nowadays are ridiculously easy.

"Recettear : An item shop's tale" did surprise me.

* In most games, dying/losing is supposed to be bad, no? Sometimes, it's fun, but it means you'll lose some sort of ressource, or go back to a checkpoint, or restart...

Recettear makes losing part of the game. You have to pay back a loan each week, and the payments steadily grow, which means you WILL probably lose the game the first time you play it, and the game will restart from the very beginning, just after the tutorial. But everything you unlocked during the first play (new stuff to sell, levels, customers, inventory) will be available for you from the beginning, meaning you'll have a very solid advantage for your new attempt.
Typically, a new player can make the last payment and get to endgame and NG+ stuff after 2 or 3 "loops"

* That also means that the game is easier if you play it "ironman like", and harder if you abuse the save/load function (since it means you're trying to win on the first loop).

* Oh, and another one : In that game, the tutorial LIES to you about some stuff. I had to discover by myself the "true" rules of the game, and realize that one of the advice the tutorial fairy gave me was actually terrible and ensured I would lose on "first loop". Don't know if it was intentionnal, though. But it was pretty satisfying to piece things together. ^^

Meh, difficult games are hardly anything new, check out chakan the forever man, its like a 2d darksouls. or the actual hardest game in the world... Wizardry 4...

which actually fits in this topic because it is a game about turning traditional rpg tropes like parties, level ups, classes, on its head, notable crimes against game design include:

Turn limit, a maximum of some fairly high number of keystrokes can be entered before you automatically lose,

A turn based movement system where an enemy pursues you IN REAL TIME, essentially another time limit.

No direct party control. the player character summons monsters which just do their own thing in combat.

No Experience The player character levels up by reaching places of power in the maze.

On the whole the game is a Puzzle game wrapped up in the guise of a Traditional CRPG. If you want to stand a chance at beating it (without guides) you better have mastered wizardry I-III first.

Its okay, I'd say Walter was overly critical. Though it is very much an oldschool adventure game, you'd have to either like the pixelated giegar art or adventure games in general to get a good game out of it.

Retsupurae did a MST3000 styled rant on the game, which is pretty entertaining if your in to that kind of thing.

Now a real bad moon logic adventure game is Curse of Enchantia. NOTHING in that game makes any amount of sense.

Hmm, unfortunately I can't think of any adventure games offhand that really break the mold, they pretty much all keep with the formula

Encounter Obstacle->Aqcuire macguffin/power/permission->Pass obstacle...
Eh, maybe thats a little to Broad a scope to consider it a "mold".

The number of key strokes allowed is very high, to the point where it is unlikely for the most significant digit to decrease from 9 to 8. (This is especially true for the PlayStation version.)

I agree that it is really a puzzle game, but the RNG can still decide to be evil and kill you. (MAKANITO, anyone?)

I believe the IBM PC version is strictly turn-based, unlike the Apple 2 and PlayStation versions.

There are a few nice things about Wizardry 4: 1. The game warns you before the point of no return, where you could be trapped if you don't have a certain item. 2. The game does not autosave, and it allows you to reload saves as many times as you like. (I actually think the game expects you to do this, especially since it offers 8 save slots and the option to copy them to another disk. In practice, I find myself using only 4 of those slots for real saves, not counting points I use for studying the game.) Wizardry 1-3 and 5 were not this nice; teleport into solid rock and you have to start over with a new party. Wizardry 4? Just reload your last save. 3. There are some very powerful pieces of equipment, including a couple items that cast a healing spell with no break chance, and even one item that is cursed but very powerful (and has no drawback other than being cursed).

One thing about the PlayStation version: It offers an automap that is free to use (although I believe it does count as a turn). Even better, the automap is preserved when (notice, when, not if) you die and reload. Anyone familiar with the game will know that this makes the game *much* easier than microcomputer versions. (Note: I am talking about Scenario #4 classic, not Scenario #4 Arrange, which changes the gameplay (notably, it allows you to control your summons).)

I was not aware there was a Playstation 1 port of wizardry, japan only eh? can't find much online but what I can find looks really nice.

So have you tried playing Darkseed yet? If you have, don't blame me on any subsequent psychological damage! That game isn't so bad it's cool, it's so bad it's that it's just bad. It's a disgrace seeing H.R. Giger's awesome 2D art being featured in such a poor gaming experience. One is better off just buying one of Giger's art books and getting lost in those intricate psychotic twisted landscapes of flesh and metal, no need to tack lousy puzzles on top of everything. It would be awesome if someone made a really good disturbing surreal adventure game with Giger's art but as far as I know such a game doesn't exist. Giger's paintings look amazing in real life, I saw an exhibit back in 2011 and was blown away. Asked the shows's organizer if Giger would personally show up but at that point he was already in poor health so I expected him to die soon which he unfortunately did last year.

Darkseed 2 is said to be better than the first but that doesn't necessarily mean much. I voted on the GOG wishlist nonetheless.
We already have Harvester, Waxworks and I Have No Mouth But I Must Scream here as well as Phantasmagoria and Bad Mojo so GOG has the genre covered nicely enough but there can always be more :)

Monkey Island.

sad to say no, I have just too many darn games waiting for my attention (cursed winter sale lol) to actively go out and seek new ones. harvester and i have no mouth are already on my backlog here :-P

I haven't played it yet, but judging from what it looks like, I'm pretty sure Little Inferno counts.