WARNING, massive spoilers ahead. Don't read if you haven't finished the game yet.

So after finishing MM1 (156 hours) I now also finished MM2 (116 hours) with hand drawn all maps, exploring everything, doing all quests... I would like to say that I finished it completely on my own but unfortunately there were 2 moments where I had to look into an online walkthrough. 1) Getting Elemental Orb out of the cave with hireling trick (why? I absolutely don't get it. What's the point?).

2) The last puzzle after Sheltem and elementals fight. It's timed and after ~10 minutes I was getting nowhere and I really, really didn't want to fight the whole cave again so I googled quickly some walkthroughs and I'm probably really dumb but I didn't understand the puzzle even after reading the walkthroughs and finishing it. One particular walkthrough guided me exactly like "first row, third word, second letter" etc... So I was able to "solve" it this way and finish the game. But I'm lost. Could someone please explain the puzzle to me, in a simple way?

You have an encrypted message. It's a simple substitution cryptogram. You have to solve it ("Preamble" is an additional clue here, but not needed; you can just solve it as a cryptogram). You get:

WE, THE PEOPLE OF TERRA, IN ORDER TO FORM A MORE PERFECT UNION, ESTABLISH JUSTICE, INSURE DOMESTIC TRANQUILITY, PROVIDE FOR THE COMMON DEFENSE...

Once you get this part done, the second part is to get the code. For this, you do need "Preamble"

P. The first occurence of P is in "People". Take the letter that corresponds to it.
R. The first occurence of R is in "teRra". Take the letter that corresponds to it.
E. The first occurence of E is in "wE". Take the letter that corresponds to it.
... etc I agree.
https://www.gog.com/forum/might_and_magic_series/mm2_how_to_get_the_elemental_orb_probably_spoilers/post7

Oh! So it is a "general cryptogram puzzle", not something specific to the game. Now I get it. And since I am from Europe (so preambule of the US constitution is not something which immediately pops in my head) and also not native English speaker, I now also understand why I did not have a chance.... :-D

Once again, thank your very much for your explanation.

Yes, just a general cryptogram. With Preamble being the additional hint.

To be honest, while I do complain sometimes about the trends in recent games, it's these type of puzzles in "good old games" that I don't miss and am happy are no longer used. Some of these puzzles were so arbitrary you had to use hint books to solve.

I did use a walkthrough too for this cryptogram, and once I found the solution I didn't feel too guilty about it.

This whole thing led me to question whether something is an exploit or not.

At one point, you get a Diamond Ring (or something of that sort), but if you try to leave (you can't just teleport because it's an anti-magic area), you are thrown into prison, but you could keep it by giving it to a hireling and dismissing them. This, at first, felt like an unintended exploit, until the Elemental Orb puzzle, where the trick I mentioned is the *intended* solution.

Wizardry Gaiden 3 has a similar puzzle, though this time I had to find the solution in a Google Translated Japanese site, as that particular game was never released in English. The problem, of course, is that this doesn't work so well for gamers who aren't in the US (and aren't familiar with the US constitution), or even worse, who are playing the game in a language other than English. (How would this puzzle work in a language like Chinese?)

I remember Darkside of Xeen having some Star Trek references in its puzzles, but at least there's enough clues for one to figure them out without cultural knowledge, and the one that involves some math doesn't have any language-dependent aspects. (With that said, DoX does have some language dependent puzzles in it.) Also. it feels unsatisfying when you have an RPG where you build up your characters and find loot throughout the course of the game, only for the game to throw a genre change at the very end, making all of that moot (and imposing a real-time timer in a game that is strictly turn-based up until that point).

Darkside of Xeen's ending also felt unsatisfying, albeit for a different reason.

I agree.

I was thinking about it a bit more and I believe that the point of JVC was to force us thinking outside the box. Problem is that I as a player did not know my goal. If the game somehow (not necessarily literally) told me that I was supposed to get the orb out of the cave then I could have treated is as a puzzle and somehow figure it out. Instead I spent a lot of time trying to find out what the game wanted me to do with the orb, because it seemed I was meant to stay in the cave until I do something with it.

Also there is another issue here - hirelings are not a mandatory part of the game. I did not use them at all during the whole game (and as I read some forums I definitely was not the only one). Therefore I had no knowledge about the fact that I can dismiss hirelings outside of inn. So even if I knew my goal I would not have a chance to figure it out.

In my opinion this is just another example of a very bad game design (there are many of them in MM1 and MM2 and they frustrated me a lot even though overally I really liked both games, even now in 2021/2022).

Well, the developers *were* inexperienced at the time, as it was still in the early days of the industry. You see bad game design in many other early games, like Ultima 1 having a real-time action minigame near the end, Wizardry 1's permadeath mechanics (one of the reasons Bard's Tale was better than early Wizardry was the removal of such mechanics), and Ys 1's poorly designed mid-game boss that's been known to drive players batty.