Dust of the Mummy

This poison is created during a mummy's embalming process, distilled from the dead creature's removed organs. A creature subjected to this poison must succeed on a DC 12 Constitution saving throw or be cursed with mummy rot. The cursed creature can't regain hit points, and its hit point maximum decreases by 10 (3d6) for every 24 hours that elapse. If the curse reduces the creature's hit point maximum to 0, the creature dies, and its body turns to dust. The curse lasts until removed by the Remove Curse spell or similar magic.