DEATH, DYING, INJURY AND WOUNDS

The mechanics of death are as good a place as any to start with any hack of an existing RPG system where combat is an important aspect. Most old school hacks and retroclones are quick to emphasise the lethality of their system in comparison with modern iterations of the world's most popular ttrpg. High risk of character death encourages more role-play, lateral thinking, and other indirect approaches to obstacles in the characters' path.

Before I layout what I want to do with our house rules, I thought it might be wise to reiterate how player death and injury is handled in a few existing systems and their "hacks"

5th EDITION (5e Basic Rules)

• PCs have a pool of hit points. Once this is reduced to 0 by lethal damage, a character is unconscious (unable to move or act) and is dying.
• There are no negative hit points, but if there is damage remaining equal to the characters max HP, the character is instantly slain ("death by massive damage")
• Dying characters make a 50/50 role each round, on a three strikes basis: three negative results lead to character death, three positives lead to the character being stabilised. 
• All attacks against the unconscious creature made from within five feet count as critical hits, which cause two automatic death save fails. e character back to consciousness and removes the "dying" status.
• Restoring one hit point through magical means brings brings th
• There are no wounds/injuries included in the basic rules, but suggestions for introducing this are made in the 5th edition Dungeon Master's Guide.

Waldo the Wizard has 3 HP remaining when the goblin crits him for 10 damage. His HP is reduced from 3 to 0 points. His max HP is 8, so the remaining 7 damage isn't quite enough to kill him outright. However, he is dying, and has to roll a D20 to make a death save. Sadly, it's a nine, and he fails... but he won't die unless he fails two further saves...

Next round, the goblin decides to attack him again, just to make sure. Because Waldo is unconscious and prone, the goblin has advantage on the roll, hitting easily, with the hit counting as an automatic critical. Crits count as two failed death saves, and Waldo is no more. In any case, the nine points of damage exceeded his maximum hp and would have caused death by massive damage.

B/X and BECMI EDITIONS 

• Characters may fight and act normally until they reach 0 hit points, when they automatically die.
• The Rules Cyclopedia included an optional rule to allow for a save vs. death ray when characters fell to 0 hit points. If they fail the save, they die. The save is then made again each round in which the character receives additional damage, and additionally every ten minutes, until restored to ten hit points.
• This rule was suggested if the DM was running a campaign without ressurection magic; however, Dark Dungeons (a Rules Cyclopedia retroclone) made it a standard rule.

Aleena the cleric has 3 HP remaining when one of Bargle's goblins crits her for 10 damage.

She dies.

But wait! The session is running Dark Dungeons!

Aleena the cleric has 3 HP remaining when one of Bargle's goblin crits her for 10 damage.

She rolls a saving throw vs. death ray and succeeds. Next round, the goblin makes another attack with its scimitar, dealing 3 points of damage and forcing her to make a second save, which she again passes. Her comrade, nameless fighter, attacks and kills her assailant. Unfortunately, he has no way of healing Aleena, so drags her back to Threshold, Aleena having to make death saves every long turn (ten minutes of game time) .

GIFFYGLYPH'S DARKER DUNGEONS (5th Edition hack, available here)

• This system follows the 5th edition rules outlined above, but with some additions.
• At half hit points, characters are "bloodied". In RP terms, this means the character has received a minor - but visible cut or bruise. Mechanically, there is mention that this is supposed to attract predators etc., but the main effect of being "bloodied" is that players may only spend hit dice to restore HP if they use a healer's kit or similar. There is therefore an additional cost to restoring HP.
• The superficial effects of a being bloodied at 1/2 hp are referred to in the basic 5e rules. It is also a status in fourth edition 
• Dropping to 0 hit points means that the PC is dying as per 5th edition above, but with some modifications:
•  The character is still conscious, but unable to move or act, apart from uttering two words.
• PCs cannot stablise themselves when making death saves.... they keep rolling until three failures have been rolled, or they roll a natural 20.
• The PC gains one level of exhaustion as a result of receiving a lingering wound..
• The effects are too numerous to list here, but they are described as "lingering", are hard to treat without magic, and their effects stack.

Sorsha of Diatonic Basslines the sorceress of draconic bloodline has 3 HP remaining when the goblin crits her for 10 damage. She was already bloodied. Her HP is reduced from 3 to 0 points. Her max HP is 8, so the remaining 7 damage isn't quite enough to kill her outright. However, she has suffered a lingering wound to her (rolls d10) chest, incurs one level of exhaustion and is dying., and has to roll a D20 to make a death save. Sadly, it's a nine, and she fails... but she won't die unless she fails two further saves...

Next round, the goblin decides to attack her again, just to make sure. Under these rules Sorsha is not unconscious so any hits are not automatic criticals. The goblin still has advantage on the roll, however, and easily strikes the fallen sorceress. The damage causes her to fail another death save. Sorsha rolls, and saves! However, she can do that all day, but if at any point she fails, she will die.

Nameless Fighter comes along to save her eventually, killing the misbegotten gobbo. A healing potion is administered, but it does not restore any hit points, merely curing the wound and removing Sorsha's exhaustion. I presume she is also stabilised.

The GLOG (Arnold Kemp's Superb B/X Hack)

The bullet points are summarised from the most recent version of Death and Dismemberment:

• At 0 hit points, PCs may still take actions as normal. 
• However, any further damage is now considered lethal, and instigates a roll on the lethal damage table.
• Two rolls are made to determine location of any wounds (d6) and their severity (d12+lethal damage + number of current injuries.

Here an example from the above PDF:

Morbo the Magician has 3 HP remaining when the goblin crits him for 10 damage. His HP absorbs 3 points, but the other 7 points are lethal damage. He rolls a d12 (getting a 9) and adds the 7 lethal damage to it for a final Severity of 16 severity. The DM rolls a d6 to for hit location, and gets a 2, indicating that the hit has landed on the leg. Severity 16 on the leg is Mangled, 2 Fatal Wounds,and 16 days of a Disabled leg.

Morbo rolls a save to see if his leg was permanently Mangled and fails it. His fucking leg is fucking chopped off, so the 16 days of “Disabled leg” ends up being irrelevant. He is currently unconscious and bleeding out, and will almost certainly die unless his allies can staunch the bleeding with some doctoring checks in the next three rounds.

Analysis

Typing out the rules for three systems, it's hard to judge each one without taking into account things like recovery and rest. Both GLOG and DD possess rules for how the effects of injuries carry over. I'd also like to run a couple of scenarios with multiple combatants to see how things pan out under each rule set, particularly the injuries and wounds features of the aforementioned.

Of the systems examined:

• I like 5e's massive damaged system and the implied negative hit points.
• Bloodied as a status from DD.
• GLOG's lethal wounds table

Right now I'm considering going with some kind of minor and major wounds tables, negative hit points, and a "bleeding out" mechanic. I still have to consider how I want to address rest and recovery first, and I've also had a lot of thoughts about hit dice...