House Rules: Death and Dying (tentative)
In the interest of making things a little more interesting, whenever I get the chance to run again, these new death rules will likely be tried out. If I like them, this post is subject to editing and will no longer be marked tentative.
On the turn after a character falls below 0 hit points, he has the choice of either immediately rolling for death saves, or waiting for the end of combat, when companions, through medicine checks and other means, may give him more chances for successful saves. As usual, 3 failed death saves, and you're dead.
Three death saves are required to prevent a character from dying, but a healing spell, while helpful, is not enough to pop somebody right up.
Each Con save for death is made at either DC 10 or however many hit points the character is negative, whichever is greater (unless Spare the Dying is used, see below).
In addition to constitution saves, there are a number of other ways to gain the saves required to prevent dying, but other than a regular constitution save, a character may only benefit from each type of death save once.
Instead of being an instant save vs death, a healing spell or potion will count as one automatic save, and subtract from any negative hit points (possibly making later saves easier if the brings the HP to 10 or less), but even if the character is brought up to positive hit points, he doesn't for sure survive (or even wake), until he has 3 successful saves. In non game mechanics terms, even magical healing is not enough to ensure the character doesn't die from shock.
Furthermore, while any further healing may effect his total HP, a character cannot benefit from more than one auto-save versus death through magical healing, with the exception of the Spare The Dying cantrip (see below).
Spare the Dying
Spare the Dying gives a dying character an immediate save success, and brings any subsequent con save to DC 10, even if they are more than 10 hit points negative. Unlike other spells, it can stack with other healing spells as a separate death save success. (I'm toying with letting Spare The Dying straight up bring a character to 0 Hp, just for simplicity's sake, but not sold, since death should still be kinda hard, right?)
Prayers for Aid
Any character who sincerely worships a deity may call for the aid of that deity to help a dying companion, with a Wisdom save at a DC of the negative Hit points of they dying character, or DC 15 (10 if a cleric), whichever is higher. A non-cleric may only do so once per day, while a cleric May do so once for each companion who goes below 0.
After combat, another character may make a medicine check, with the same difficulty as a constitution save from the dying character (DC 10 or negative hit points, whichever greater) to give a successful death save (cannot be done during combat, as 6 seconds isn't enough time to check someone's injuries and stabilize them).
A character only becomes conscious if he makes three death saves AND has positive hit points.
Immediate Saves versus Death
There are two exceptions to the general requirements that a character make three saves to survive and gain consciousness.
A cleric may bring a character immediately back from death, alert and ready to fight, requiring no saves, by channeling divinity.
A warlock or other character with access to a magical patron may call on that patron to save a companion from death with no save, often with extra, unpredictable effects. For example, the saved character may find that he is temporarily infused with that patrons power, gaining new abilities, or maybe transformed into a monstrous beast for the rest of the fight. And of course the invoker and invokee run the risks of extra planar corruption as normal (a sure thing for the invokee, and a 50% chance for the one effected; see house rules for warlock pact magic).