The Ring of Second Life (5e Equipment)

Ring, Very rare (major) (requires attunement)

A thin silver-plated ring set with a large crimson gem, cut in the shape of a heart.

While wearing the ring, when you fail a death saving throw, it then activates. You immediately regain 5d4 hitpoints, return to consciousness, and gain 5d4 temporary hitpoints. The ring then burns a scar into the finger and shatters into innumerable pieces, rendered nonmagical.