Painting from Waterdeep novel.
Prerequisite: You must carry a curse that can be lifted only by a quest or similar great undertaking, or have the Cursed Birth background.
Benefit: You gain spell resistance equal to 5 + your character level, as the curse interferes with all magic. Unlike most spell resistance, it can't voluntarily be lowered, though your own spells and magic items still automatically affect you.
Goal: Your curse is lifted or you are able to purge the corruption of your fiendish blood (the circumstances of either vary widely based on the nature of the curse, and are up to the GM).
Completion Benefit: You lose the spell resistance described above. You gain spell resistance equal to 11 + your character level, but only against harmful enchantment, necromancy, and transmutation spells and spell-like abilities—your aura resists further attempts to curse you. Harmless spells automatically bypass this spell resistance whether you desire it or not. This spell resistance can be voluntarily lowered.