Living Curses

Infested by broken spirits that curse the item, these spirits power the curse through their lifeforce and desires, causing bonuses and penalties to match. Due to the nature of the curses, they cannot be removed through normal methods, requiring some measures of sacrifice to kill the origin, or other means varying by spirit.

Wailing Potion of Healing

Potion, rare, living curse

A healing vial full of a dark red blood-like substance, it's in a state of perpetual screaming. When closed, the screaming is largely muffled, the vial shaking violently from the restricted noise. The healing factor of the potion is untouched, keeping the properties of whatever tier of potion it originally was. After drinking the full potion, the creature is cursed with Blood of Wailing, a shrill ringing beginning in their ears that doesn't quite go away.

Blood of Wailing: Whenever a creature that is cursed in this way has less than its full hit points, its blood begin to scream in pain. The creature has disadvantage on Wisdom (Perception) checks that rely on hearing, and cannot hear anything quieter than a shout.

Retreating Screams (Curse Progression): If the creature's has less than half of its hit points left, the screaming intensifies as the creature's wounds shriek. The creature's blood protests at the injuries of it's host, bloody wounds being restored as the curse tries to keep itself contained. This shrieking is clearly audible to creatures within 30 feet of the cursed creature, while the cursed creature itself is considered deafened due to the noise. In addition, the cursed creature cannot take the Hide action while its wounds are shrieking, but the creature regains 1 hit point at the start of each of its turns.

This curse ends if the creature is reduced to 0 hit points or finishes its second long rest since becoming cursed in this way.

Credit to probablybadrpgideas for the concept.

Living Ring of Life

Ring, rare, living curse (requires attunement)

A beautiful, thick ornate ring of silver featuring three white gemstones on it's face, the gems giving off a faint gray mist when charged. While unknown in origin, jewellers may find the ring familiar to magic ones told in tales, ones adorned with ruby meant to grant the wearer long life. Once worn & attuned, the ring awakens, digging into the flesh of the wearer and lowering their max HP by their proficiency bonus. After a short rest, the living ring absorbs the stolen lifesource into its gems, regaining it's maximum of 1 charge.

Selfish Savior. In order to protect it's lifesource, the ring expends 1 charge when the wearer falls below 0 hp, healing the wearer equal to their proficiency bonus at the start of their next turn.

Should harm come to the ring, so should harm come to the host. Attempts to break or remove the ring are met with pain, and should any be successful, the ring will remove the finger with it. Any charges are immediately discharged on removal into a cloud of white mist, removing previously imposed max HP penalties.