Rotting Curse of Urfestra

3rd level Corrupt transmutation spell.
Casting time 1 action.
Touch range.
Components V, S.
Duration Instantaneous.
Book of Vile Darkness

One living creature touched must make a CON save. On a failed save, the subject's flesh and bones begin to rot. The subject’s maximum HP is reduced by 3d6 every hour until the subject dies or the curse is removed with a Remove Curse or similar spell.

Corruption Cost: 1d4 STR drain

Any spellcaster that prepares spells can learn these spells. Each spell list has an alignment attached to it. If a creature of a different alignment casts one of these powerful spells, their alignment shifts towards the alignment of the spell by one step. Each spell has a corruption cost that is paid when the duration of the spell ends or according to the spell’s description. If the cost is ability damage, it is restored when the caster finishes a long rest. If the cost is ability drain, it does not recover until the creature receives attention from a Greater Restoration spell.