Shortly before town of Honmur was consumed in a raging conflagration, an expedition had returned from the nearby tomb. Within its depths they found a chest full of valuable gems. I have been fortunate to recover one of these gems from the ruins of the town; it has already shaved my life from the ambush of the mad survivors of the town. I feel at peace when I hold the gem, I think it will prove invaluable on my travels.
-Tangar the Cursed, last journal entry
Splinter of Gygaxia
It bears an emblem of a snake etched upon its surface. In its dormant state, it gives off no magic aura and identifies exactly as a normal gem worth 50GP would identify.
Though there is no visible sign, the gem bonds with the last creature to touch it. While it is bonded in this way the creature gains the Cheat Death ability. The crystal bestows no sign that it has imparted this ability or even that it has bonded with the creature.
Cheat Death – Triggers when the bonded creature fails a Death Saving Throw.
The first time a creature uses this ability: it regains 10 HP instantly. If the creature is a Player Character, they can no longer be awarded Inspiration for performing good actions. All Insight checks to determine a creature’s motives or truthfulness are made at a disadvantage. The crystal now vibrates somewhat more energetically.
The second time a creature uses this ability: it regains 20 HP and, if applicable, one first level spell slot. If the creature is a Player Character, they can now only be awarded Inspiration for evil actions. In addition, they begin to hear whispered promises of power; solutions to their dilemmas are carried to their ears, borne on the faintest winds of hell.
The crystal is now warm to the touch. It identifies as having a strong aura of necromancy.
The final time a creature uses this ability: it is time to pay the toll. Instead of failing one death saving throw, the creature fails two. If the creature dies while bonded to the crystal in this way, the crystal disappears and the creature’s body melts away in a fiery inferno to be reborn as a Marlith (see MM page 61).
If a new creature touches the crystal, it bonds with that creature; however, this does not reset the effects of the Cheat Death ability. The only way to remove the effects is with a Wish Spell or by destroying the Shard of Gygaxia.