One of the optional rules in Chapter 3: Avernus is Bargain Basement Death Saves (page 78, Descent into Avernus). The concept is that if a character fails a Death Saving Throw in the Nine Hells, an archdevil may telepathically contact them and offer to save them from death if they agree to do some undisclosed task in the future.
While the idea is awesome, the implementation leaves something to be desired.
I’m actually a fan of making these a secret, so only the downed player even knows of the deal being offered, and whether or not they have accepted it. To do this you could either privately message the player (in a whisper, Discord private chat, or even text to their phone), telling them to reply in kind.
This means they then try to keep their deal secret from the other characters, which could make for some great roleplay opportunities. It also will be fun when the next person goes down and gets a deal – leaving them wondering “Did Jane also get a deal like this? Did they take it?”
By the book should you accept the deal, the benefit is a natural 20 on your next Death Saving Throw, so automatic revival at 1 HP.
The best way to do that, if you are trying to keep it a secret is to have all Death Saving Throws be done in secret just between the player and the DM (or for even more chaotic fun, just done by the DM in secret). Obviously you would need to set that precedent at the start of the campaign, or it’s kind of weird.
Failing that, you could just have it clearly be something extraordinary, but intentionally fail to elaborate and pretend to even leave the player without answer to why it happened.
“As you fail your last saving throw, your body convulses as if surging with energy. Your eyes open, barely escaping death – somehow.”
Obviously they are ‘in on it’, but it gives them an opportunity to feign ignorance. If you avoid theming it as something dark or evil happening, they could possibly even claim it to be a divine blessing from their god, or other benevolent act.
This also allows you to give a mechanical bonus for accepting the bargain, related to the archdevil, which lasts until they complete the task (see below). You could have the archdevil renegotiate a further deal upon its completion, to maintain the boon for a new task, or escalate even further.
The task themselves are meant to be “usually simple and straightforward” and take the effect of a geas spell with no save allowed. If you somehow break the bargain, such as with a remove curse spell, then you immediately fall down dying again.
This is super weak. Not only is geas a measly 5d10 psychic damage once per day easily survived and healed through, but being able to remove it at a convenient time and immediately heal out of death saves is not exactly tricky.
Instead how about breaking the deal causes your soul to be forfeit, until you accept an even harsher bargain or gain it back due to divine intervention or a wish spell.
The daily damage could simply be changed to a smaller amount every hour you aren’t actively working towards the task and 1 level of Exhaustion each day. It is much harder to survive damage spread out every hour and the harsh stacking penalties of exhaustion, but still not immediately crippling or an instant death.
Bargain-Basement Death Saves: When you would need to make a death saving throw while in Avernus, you are contacted telepathically by an Archdevil. If you accept their task the archdevil will immediately restore you to full HP and present you with their boon. Should you stop working towards the task you will begin taking 1d10 psychic damage every hour, as well as gain an unremovable level of exhaustion every 24 hours. If you somehow remove the effect your soul is forfeit; you cannot be brought back to life without divine intervention or the permission of the archdevil.
Here is a list of bargains from each of the archdevils mentioned in the campaign. You may wish to add more to highlight other archdevils/layers of Hell.
If you keep this list to hand, simply cross them off when you use them – writing a new one to replace it during your next prep session. If you go through all these deals in a single session, maybe the archdevils just no longer consider the characters worth saving.
I can’t see many players accepting an unspecified task, as who know what that might even be… so I’ve included the task in the bargain. You could always reveal it after they accept, should you prefer it to be unknown.
“Weakling. Have you given up your will to fight? I can make you stand strong, ready to charge gloriously against your enemies once more. All I ask in return is that you kill demons – a dozen sent back to the Abyss – a service to all creatures everywhere.”
Boon: Your eyes blaze with a burning radiance, allowing you to reroll a single Attack roll (including Spell Attacks) once per long rest.
“I could save your soul, bringing you back to life and giving you the tools you need to destroy your enemies. Red Ruth owes me tribute, collect it from her and bring it to my forge, and my gifts shall be yours.”
Boon: You regain consciousness, your weapon now glowing with veins of hellfire. It counts as being made of infernal iron, sheds dim light in a 5-food-radius and counts as a +1 magical weapon. (If a spell caster consider giving them a similar +1 Wand of the War Mage)
“Mortal, tremble beneath the majesty of the Dragon Queen. You suffer needlessly, dying like a maggot in the dirt, yet in my service you could bask in eternal glory. The wimp Uldrak possesses an item of importance to me – the Orb of Dragonkind. Kill him and deliver it to my champion in his dark tower. Uldrak must not survive.”
Boon: You awaken with dragon fire coursing through your veins. Once per long rest you may spew forth magical energy from your mouth, dealing 4d6 acid, cold, fire, lightening or poison damage in a 15-foot cone. Targets who succeed on a Dexterity saving throw take half damage.
“The battle of Avernus barely scratches the surface of the Nine Hells. You are destined for so much more. Let me bring you back from the brink of death and bestow upon you great magical power – and all you need do is speak with the wizard Mordenkainen in his tower. Convince him to speak with me at the Mirror of Mephistar.”
Boon: The mysteries of the arcane unravel inside your mind – giving you a glimpse of the weaves infinite complexities. Any time you make a saving throw against a spell you gain temporary hit points equal to twice the spell’s level.
“My friend, my friend, why are you so down? Your soul is very heavy and cold, barely fading away. Let me give you a hand back up! In exchange you only need to wreck the War Machine of one of the Warlords scattered across this blasted wasteland, a single rod in the wrong place, a redirected pipe will do just fine, for we all need repairs do we not?”
Boon: Your hands gain the ability to flex backwards as well as forwards, You gain +5 to your Sleight of Hand checks to sabotage or fix a War Machine once per long rest.
* Mahadi is actually working for Asmodeus, so while not an archdevil himself, he commands the power to deliver bargains to further his master’s goals.
Mahadi’s bargain was sent to me by Shadows_Assassin