How to die in D&D

Brown Book D&D (1974)

As an addon to the wargame Chainmail, in which heroes were considered units expendable in pursuit of victory, the original D&D publication barely mentions death at all, merely adding a note to the Dice for Accumulative Hits (Hit Dice):

This indicates the number of dice which are rolled in order to determine how many hit points a character can take, [...] the number of points of damage the character could sustain before death.

Hit points were low, at slightly more than 1d6 per level for Fighters, slightly less for Clerics, and roughly 1d6 every two levels for Magic-Users. Death was a pressing concern at all times, as all weapons also did 1d6 damage and monsters attacked once for every HD. An evenly-matched fight almost certainly meant deaths on both sides.

Compared with later editions, death was also instantaneous. At 0hp, you died. No time for the rest of the party to win the fight and come to your aid. This simplified the survivors' decision to flee the scene to a simple question of the value of the dead PC's equipment...

On the subject of healing, only magical healing and recovery is discussed. Clerics and healing potions were essential, and natural healing left to the DM to adjudicate. A ring of regeneration, however, would bring the user back from death unless destroyed like a troll, a theme that would come back in Gygax's other work. Raise dead existed, with a brief mention that Constitution determines the chance of success - if we are to assume this meant 'adversity' as mentioned in the Abilities section, a PC of average Constitution seemed to have about 70% chance of survival after being raised.

Basic (1977 - 1983+)

Basic continued the tradition of death at 0hp. The boxed Mentzer red book player's guide explains that as part of the single-player adventure, including a special note explaining atypical rules for that adventure:

If you are struck down to zero hit points or less, you can grab your potion - if you still have it - and drink it before you pass out. It will cure you somewhat, but only back up to 4 hit points. If you don’t have the potion left - sorry, but you are dead! (Special note: In group games, you will not be allowed to do this. Zero hit points indicates death, with no extra time to do anything.)

And the frequency of death is even addressed early, if the player dies in that demo dungeon:

Your character has been lost in the dungeon. Don’t be upset; it can happen in any DUNGEONS & DRAGONS game, and often does, through no fault of yours.

While natural healing isn't explained, resting at an inn for "a day or two" seems to be enough for most low-level PCs. As for magical healing, at this low level only potions and spells of cure light wounds are detailed.

Expert adds the previously-mentioned raise dead spell, though the risk of failure is removed and no limit to resurrections is mentioned. This significantly changed the flavor of the game, once a cleric reached 10th level, or access to the spell was obtained through other means. Where in OD&D a raise dead might bring a PC back to life a couple times, now so long as the party cleric survived, anybody could be raised indefinitely. Not only did this make combat far less risky for individual PCs, once death had occurred in a combat, it became vital to reclaim the body before fleeing, preferably in one piece!

Expert also added the ring of regeneration but explicitly stated that it ceases to work when the wearer's hit points drop to 0 or less.

Companion and other books extended access to raise dead - the first Gazetter suggests the cost of employing a 10th-level cleric as a Chaplain at a stronghold should be 1,000gp!

AD&D First Edition (1979)

The rules of death, dying, and healing in AD&D First Edition's Player's Handbook have much more in common with Gygax's early work than the Mentzer/Holmes Basic line.

Damage is meted out in hit points. If any creature reaches 0 or negative hit points, it is dead. Certain magical means will prevent actual death, particularly a ring of regeneration (cf. MONSTER MANUAL, Troll).

Gygax kept the lethality of the original game intact; low-level AD&D characters were expected to die just as frequently. He also kept his curiously powerful ring of regeneration which must have resulted in a common trope of the party fighter dying, the rest of the party fleeing, and the fighter waking back up an hour later, alone in a room full of dangerous monsters...

For the first time, rules for natural healing were detailed: PCs heal 1hp per full day of rest up to day 30, and then 5 per day after. This option was really only intended for parties without a cleric, given that even a 1st-level cleric had access to faster magical healing.

Raise dead continued to be a risky proposition, retaining the saving throw to survive the ordeal and the limit on the number of times a character can be brought back to life (equal to the character's initial Constitution, regardless of magic). It also added a new drawback: every time a character is resurrected, they permanently lost a point of Constitution, making future resurrections more difficult.

AD&D Second Edition (1989)

Second edition also kept the tradition of instant death at 0 hit points.

Natural healing through rest comes with two options; resting while traveling regains 1hp per day, while a full day of bed rest regains 3hp (adding Constitution bonuses each full week).

Being raised from the dead retained the saving throw and Constitution loss, though the hard limit was removed, allowing PCs to regain lost Constitution and be fully restored through items like a manual of health or even a wish.

D&D Rules Cyclopedia (1991)

While normally I group this under the Basic heading, this appears to be new rule created for this book. In Chapter 19: Variant Rules, two optional rules are provided.

First, it presents an option to simply remove all magic that raises characters from the dead. This helps to restore the threat of death to parties with a cleric level 10 or above, and reduces the odds of a PC reaching truly staggering levels.

Second, it suggests that if using the first rule, the DM should adopt a change to the death rules, such that a character doesn't necessarily die at 0hp. Instead, a save vs death ray is made immediately and every 10 minutes; so long as the saves are made, the PC is still alive and can be revived with healing magic or the Healing skill (added in Gazeteer).

D&D Third Edition (2002)

Third edition canonized the optional rule from second edition and elaborated on it further:

When your hit point total reaches 0, you’re disabled. When it reaches –1, you’re dying. When it gets to –10, your problems are over — you’re dead.

At 0hp, a character can limp around, but not take any standard actions (like attacking, casting a spell, or anything strenuous) or suffer 1 point of damage and become unconscious.

Below 0hp, a character starts bleeding, losing 1hp per round, until -10hp, at which point the character dies. There's a 10% chance each round that the bleeding stops (or at least slows to once per hour), and any external healing has the same effect. From there, magical or natural healing can recover the character, though without aid it is unlikely.

Natural healing yields 1 hit point per level for eight hours of full rest; a full day of rest doubles this.

A ring of regeneration ends up behaving quite similarly to original D&D as a consequence of these rules, as it will stop the bleeding and return the character to consciousness as it regains hit points.

Magical resurrection is less chancy than previous editions, requiring no special save mechanic to survive, but all but the most powerful forms result in the loss of a single level. The most powerful form, the level 9 true resurrection, has no downside, but costs 25,000gp in diamonds. Very high-level parties may scoff at that tiny expense to bring back a party member, leading to the cheapening of death as seen in the Basic lineage. In my own game, I've addressed this by making diamonds a somewhat limited resource; even a big city can only provide so many diamonds for PCs to purchase at one time.

D&D Fourth Edition (2008)

Fourth edition does away with the disabled condition, but keeps the "down and bleeding" rules for when a character reaches 0hp. Without help, the character makes saving throws each round; three failures means death, but one significant success allows the spending of a "healing surge" to recover hit points (from 0) and wake back up. While dying, any healing restores hit points as if at 0hp, resulting in recovery.

Healing surges are a new resource created in 4e; every character has a number of them per day based on class and Constitution. The surges can be used by the character themselves (once per encounter as an action called "second wind" or while taking a short rest) or used by other characters casting healing spells on the character. This resource was reportedly meant to both remove the reliance on dedicated party healers, but also to regulate the pacing of adventures by treating it like any other expendable resource. However, it's also very abstract, not representative of anything within the game fiction, and many felt it was too unlike any previous edition.

Natural healing is simply a matter of resting and spending healing surges; a full night's rest fully heals any character, removes almost all negative status effects, and recovers all powers.

Raise dead made use of the new Ritual system, in which anybody could purchase ritual books from a marketplace and use them. A newly-raised character suffers some minor penalties (-1 to most rolls) until the characters "reaches three milestones" - another new concept pertaining to adventure progression. This reduces recovering a character to a matter of going to town, spending some gold (based on the 'tier' or level of the character) and spending 8 hours casting a ritual. Even a level 1 party can do this, so long as they have 500gp to spend.

D&D Fifth Edition (2014)

Despite the lukewarm reception of Fourth edition, many of the death, dying and healing rules were retained to some degree.

Being reduced to 0hp knocks a character unconscious. Each round thereafter, a roll with 55% chance of success is made; collect three successes before three failures to become stable and avoid dying. During this time, any healing (magical or skill) returns the character to normal. There's some other rules surrounding the death saves process, but on average most characters will recover rather than expire unless further damaged.

Healing is primarily done via a 'short rest' mechanic similar to Fourth edition; rather than spending healing surges, however, the character spends recovery hit dice (the same number and type the character rolled for hit points) to recover hit points; these hit dice are recovered after a long rest, which also heals all damage and most status effects. Magical healing remains useful for combat situations and doesn't rely on the recovery hit dice mechanic, however.

Returning characters from the dead is available at a surprisingly low level; 5th-level clerics can cast revivify to raise somebody that died in the last minute with no negative effects. Characters dead for longer need a more powerful spell like raise dead or resurrection, which (like Third edition) require some gold expenditure to obtain diamonds and levy some temporary penalties on the subject and/or caster that can be removed with rest.

Summary

The rules for how to die in each edition reflects that edition's philosophy of play. In some editions, death is meant to be easy and cheap, reflecting a pathetic aesthetic or suggesting combat as brutal and dangerous and to be avoided when possible. In other editions, combat is glorified, and the roles of PCs within combat is even more glorified, so much so that random and pointless death no longer fits the gameplay.

Other quirks, like the availability, cost and risk of magics used to raise dead characters, point to finer nuances of play; death came easy for Basic D&D characters, but after the "character funnel" of low-level play, death became a trivial annoyance for all but the worst cases, and an annoyance you could keep a cleric on retainer back home to deal with.

All of this also influences play style for PCs; players who know death is hard and resurrection is easy will behave much differently around powerful monsters. The same players will have a much different view of combat and risk if they experience six months of character-funnel play.