Are there any self-imposed rules you apply when playing these games?

Here are mine for World of Xeen:

1. No training in Castle Kalindra or Olympus. This stops leveling before money becomes an issue and means I can actually use permanent level boosts without worrying about increasing costs.

2. Pretend that the +50 stat boost in Corak's space ship doesn't exist. This way, I can actually use other stat boosts during the course of the game.

(Also, as I mentioned in another topic, I tend to not use armor, as it tends to be more trouble than it's worth.)

For World of Xeen:
- I don't venture to Darkside until Lord Xeen is dead.
Globally:
- I don't use a single consumable (exception - Black Potions in MM VI-IX).
- If one character reaches 0 HP, it is Game Over for me. Reload.
- I don't use Banks.
- I don't directly kill friendly NPCs. Armageddons don't count. Lured monsters don't count either.

I consider this a fair rule, although I tend not to use it myself.

Also, I would break this rule if I am more interested in Darkside than Clouds. Personally, I don't like these rules. Not using consumables, IMO, really does take away from the game. Similarly, the 0 HP rule takes away one of the series's more interesting aspects. (Also, I don't like having to constantly reload.)

Why do you have that 0 HP rule anyway? What purpose does it serve?

I have never encountered a situation in the Might and Magic games I have played where the game even gave an option. (Well, I could argue Sharla in MMV, but the question is what counts as friendly there?)

I do use Banks, but my play style tends not to let that much time pass, mainly because I don't train that often.

(Of interest, in MM3 you can take advantage of the bank and the place that gives you temporary jobs to get about 1.5 billion gold, then create new characters (because your old ones are now too old to adventure), and then use the Gold->XP fountain to get everyone up to level 200.)

If inventory is nigh infinite, I hoard consumables in case of some extremely hard encounter (which I win without consumables anyway). Otherwise I just sell all the consumables.

I got used to these rules after being spoiled by some friends-hoarders in Ultima Online, and after very pathetic 1st playthrough of Yendorian Tales III (no gold to pay to gold-hungry obelisks, rendering game unwinnable after 40 hours of gameplay). Also using items often feels like cheating (e.g., potion spamming to victory). I like seeing my characters having same amount of EXP. Also thinking about some characters as being risen from the dead gives me uneasy feeling. I understand it is game, but I want to keep deaths at absolute minimum :) Might and Magic VI-VIII allow that. In MM VII (and VIII probably too) you can lure nasty monsters into peaceful village, very useful on newbie island, because otherwise you have to pay for harp and you could use all the bonus gold at start of the game. That is close to cheating. Same as making new characters, taking their gold and selling their stuff, removing them from party and recruiting new ones... Making entire kingdoms bankrupt by withdrawing billions of gold from central banks, robbing potential heroes of all their belongings, putting potential heroes to lifetime slavery... It might make you wonder who is true villain - Lord Xeen or you?

I have a tendency to hoard consumables and never use them, but I am working to try and change that tendency, at least on some games. In Final Fantasy V, for example, throwing scrolls can kill enemies quickly, giving you more money than you spent on the scrolls (especially if you have good Magic Power).

Your unwinnable example I would consider to be the game's fault. Also, when item use feels like cheating, I again consider it the game's fault.

One game design idea I have is what I call Metroid-style consumables. In certain spots, you find consumable items, and that increases the maximum number you can carry. Once you use the item, you can get it back from shops or enemy drops, but are still limited to the number you found. (Think of missiles in Metroid for an idea of how it works.)

Another idea I have is putting immediate pickups into an RPG. Basically, they work like hearts in Zelda games: when the item is picked up, it has an immediate benefit (like healing your party), but you can't keep the item for later use. In the MM series, reaching 0 HP is not death, and such characters still gain experience points. In 3-5, a character dies only on reaching -max HP. (Also, it has to be from damage; Half for Me counts, but HP overflow from a fountain in 3 or Swords of Xeen does not.)

In the game I'm thinking of writing, dead characters will still gain the closest counterpart to XP that my game has, and death will not erase stat/skill gains from actions performed while the character was alive. I have played a few games where death doesn't prevent XP game (like the Android/iOS game DotQuest, and in a sense Saga Frontier 2) and I prefer it that way.

As a side note, when I first beat Dragon Quest IX, my main character was dead at the end of the battle. However, she gained enough XP to level up from the final battle. In DQ9, you can't level up if you're dead, but can still gain XP, so she had more than enough XP to level up when I started the post game. (Also, the ending automatically brought her back to life with 1 HP.)

It is possible to replicate same situation with standalone Might and Magic IV too. if you will fail to get 50000 Gold until very late in the game, you are screwed (well, you can work your characters to death and make new ones... but then they won't be able to kill anything).

Actually it is possible to screw yourself in any game with finite resources and render game unwinnable. It is just easier to do so in some games, and harder - in others.

Yendorian Tales II/III are very good MM 3-5-alike games. They probably were made with approach: play and see how far can you get. My poorly leveled characters weren't able to kill even a single fire dwarf without deaths. I cheated and even with extensive cheating I wasn't able to scratch phase titans later on. However, upon taking closer look on game systems, gameplay was feeling very rewarding. I didn't play much of Zelda, but I guess it works a bit similar to Final Fantasy XII. At 2nd+ Chain Level you have chance to get small heal or even Protect/Shell after collecting loot form defeated enemy..I don't think it can be considered as "real" consumable item. MM simply gives you a bit breathing room to recuperate from lethal damage. Still, characters with 0 HP don't show any sign of life and can't act... Something makes me thinr, that I'll start working on dungeon crawler sooner than you on your game :)

The way it works in Zelda is as follows:
The combat is completely collision based. (In other words, these games are action games, not RPGs.)
You start the game with 3 hearts of life. When you take damage, you lose your hearts. (In Zelda 1, this was indicated by hearts turning white.) When you lose all your hearts, you die. (In other words, hearts are your HP.)
Randomly, enemies (and later in the series, things like pots) will drop small hearts when defeated. Pick it up before it disappears and you will recover one heart.
The original Zelda also has clocks, which when picked up, freeze every enemy on the screen and make you invincible until you leave the screen. Some Zelda games have magic bottles which refill your magic meter.
The Metroid games (2d sicescrollers) do something similar; enemies drop balls that refill your energy.

So essentially, this is a gameplay mechanic not typically associated with RPGs that might work in an RPGs. In any case, I call them immediate pickups instead of consumables. Actually, the way I see it, such characters are unconscious, and while unable to act, are still alive.

I would recommend playing Wasteland to get another game's take on handling injuries and 0 HP. A character whose CON (the game's counterpart to HP) reaches 0 or just below is unconscious and unable to act (but invincible) for a few rounds. A character who takes more damage is seriously wounded and needs medical attention, or her condition will worsen. There is no magic, but there are two skills that can help the character. Alternatively, you can find a Doctor, but that may take too long and the character may die, which can only be cured by being hit by poison gas in the gas chamber (which can only be done once and is probably not intened.)

According to the game manuals, this is correct. Characters are knocked unconscious when they fall below zero HP. They are still alive, but knocked out, so they can't act. If they take more damage they may die, or even be obliterated.

So if the reasoning for the "reload when hitting zero HP" rule is related to death, then it wouldn't apply in these situations. It would only apply when characters are actually killed, which is shown by their portrait turning into a tombstone.

In my opinion, the unconsciousness mechanic can add some interesting strategy. Unconscious characters are easy to restore, they just need some healing or some rest, but they are vulnerable and if they are killed it is much harder to get them back (or impossible, if one is using a "no death" self-imposed rule). Therefore, during combat it's important to have healers reviving unconscious characters so they can get back in the fight before they are killed. I found this lent an interesting strategy to the tougher encounters.

Then again, if someone is already playing with a self-imposed rule of reloading whenever a character falls below zero HP, then even the strategies discussed above may seem too easy.

If you use the "0" hit point rule, then wouldn't stone or preservation be better to keep them on the right side of zero. I wouldn't want to keep a healer busy if a player is passing out every other turn.