Daemogoth Titan

Daemogoth Titan
Daemogoth titans are towering monsters that blight the land around them. A daemogoth grows in power over the course of decades spent feeding on sorrow and draining life from nature. Eventually that growth turns the daemogoth into a titan.
The titans maintain their lesser cousins' ability to trade magical power for a mortal's pain, but they tend to demand more punishing suffering in exchange for their pacts or knowledge.
Barbed Gifts
When a supplicant piques a daemogoth titan's interest, the titan can grant a blessing to the supplicant (see 'Supernatural Gifts 'in the Dungeon Master's Guide). As long as the creature has the blessing, it must expend and roll two of its Hit Dice whenever it finishes a long rest. It takes psychic damage equal to the total rolled, and its hit point maximum is reduced by an amount equal to the psychic damage taken. This reduction lasts until the creature finishes its next long rest. The creature dies if this effect reduces its hit point maximum to 0. The blessing can be removed only by a wish spell.